Package groovy.sql

# Class Sql

java.lang.Object
groovy.sql.Sql

All Implemented Interfaces:
  `AutoCloseable`

Direct Known Subclasses:
  `DataSet`

public class Sql extends Object implements AutoCloseable
A facade over Java's normal JDBC APIs providing greatly simplified resource management and result set handling. Under the covers the facade hides away details associated with getting connections, constructing and configuring statements, interacting with the connection, closing resources and logging errors. Special features of the facade include using closures to iterate through result sets, a special GString syntax for representing prepared statements and treating result sets like collections of maps with the normal Groovy collection methods available.

#### Typical usage

First you need to set up your sql instance. There are several constructors and a few `newInstance` factory methods available to do this. In simple cases, you can just provide the necessary details to set up a connection (e.g. for hsqldb):

     def db = [url:'jdbc:hsqldb:mem:testDB', user:'sa', password:'', driver:'org.hsqldb.jdbc.JDBCDriver']
     def sql = Sql.newInstance(db.url, db.user, db.password, db.driver)

or if you have an existing connection (perhaps from a connection pool) or a datasource use one of the constructors:

     def sql = new Sql(datasource)

Now you can invoke sql, e.g. to create a table:

     sql.execute '''
         create table PROJECT (
             id integer not null,
             name varchar(50),
             url varchar(100),
         )
     '''

Or insert a row using JDBC PreparedStatement inspired syntax:

     def params = [10, 'Groovy', 'http://groovy.codehaus.org']
     sql.execute 'insert into PROJECT (id, name, url) values (?, ?, ?)', params

Or insert a row using GString syntax:

     def map = [id:20, name:'Grails', url:'http://grails.codehaus.org']
     sql.execute "insert into PROJECT (id, name, url) values ($map.id, $map.name, $map.url)"

Or a row update:

     def newUrl = 'http://grails.org'
     def project = 'Grails'
     sql.executeUpdate "update PROJECT set url=$newUrl where name=$project"

Now try a query using `eachRow`:

     println 'Some GR8 projects:'
     sql.eachRow('select * from PROJECT') { row ->
         println "${row.name.padRight(10)} ($row.url)"
     }

Which will produce something like this:

     Some GR8 projects:
     Groovy     (http://groovy.codehaus.org)
     Grails     (http://grails.org)
     Griffon    (http://griffon.codehaus.org)
     Gradle     (http://gradle.org)

Now try a query using `rows`:

     def rows = sql.rows("select * from PROJECT where name like 'Gra%'")
     assert rows.size() == 2
     println rows.join('\n')

with output like this:

     [ID:20, NAME:Grails, URL:http://grails.org]
     [ID:40, NAME:Gradle, URL:http://gradle.org]

Also, `eachRow` and `rows` support paging. Here's an example:

     sql.eachRow('select * from PROJECT', 2, 2) { row ->
         println "${row.name.padRight(10)} ($row.url)"
     }

Which will start at the second row and return a maximum of 2 rows. Here's an example result:

     Grails     (http://grails.org)
     Griffon    (http://griffon.codehaus.org)

Finally, we should clean up:

     sql.close()

If we are using a DataSource and we haven't enabled statement caching, then strictly speaking the final `close()` method isn't required - as all connection handling is performed transparently on our behalf; however, it doesn't hurt to have it there as it will return silently in that case.

If instead of `newInstance` you use `withInstance`, then `close()` will be called automatically for you.

#### Avoiding SQL injection

If you find yourself creating queries based on any kind of input from the user or a 3rd party application you might wish to avoid the pure string method variants in this class. While this is safe: `sql.firstRow('select * from PersonTable')` This example is potentially at risk of SQL injection: `sql.firstRow('select * from PersonTable where SurnameColumn = ' + userInput)` This in turn will be fine if '`userInput`' is something like 'Smith' but maybe not so fine if '`userInput`' is something like 'Smith; DROP table PersonTable'. Instead, use one of the variants with parameters and placeholders: `sql.firstRow("select * from PersonTable where SurnameColumn = ?", [userInput])` or the GString variants which will be converted to the placeholder variants under the covers: `sql.firstRow("select * from PersonTable where SurnameColumn = $userInput")` or the named parameter variants discussed next.

#### Named and named ordinal parameters

Several of the methods in this class (ones which have a String-based sql query and params in a List<Object> or Object[] or Map) support named or named ordinal parameters. These methods are useful for queries with large numbers of parameters - though the GString variations are often preferred in such cases too. Reminder: when you see a variant with Object[] as the type of the last parameter, Groovy allows vararg style parameters so you don't explicitly need to create an Object[] and if the first parameter is of type Map, Groovy supports named arguments - examples of both are contained in the examples below.

Named parameter queries use placeholder values in the query String. Two forms are supported ':propname1' and '?.propname2'. For these variations, a single model object is supplied in the parameter list/array/map. The propname refers to a property of that model object. The model object could be a map, Expando or domain class instance. Here are some examples:

     // using rows() with a named parameter with the parameter supplied in a map
     println sql.rows('select * from PROJECT where name=:foo', [foo:'Gradle'])
     // as above for eachRow()
     sql.eachRow('select * from PROJECT where name=:foo', [foo:'Gradle']) {
         // process row
     }

     // an example using both the ':' and '?.' variants of the notation
     println sql.rows('select * from PROJECT where name=:foo and id=?.bar', [foo:'Gradle', bar:40])
     // as above but using Groovy's named arguments instead of an explicit map
     println sql.rows('select * from PROJECT where name=:foo and id=?.bar', foo:'Gradle', bar:40)

     // an example showing rows() with a domain object instead of a map
     class MyDomainClass { def baz = 'Griffon' }
     println sql.rows('select * from PROJECT where name=?.baz', new MyDomainClass())
     // as above for eachRow() with the domain object supplied in a list
     sql.eachRow('select * from PROJECT where name=?.baz', [new MyDomainClass()]) {
         // process row
     }

Named ordinal parameter queries have multiple model objects with the index number (starting at 1) also supplied in the placeholder. Only the question mark variation of placeholder is supported. Here are some examples:

     // an example showing the model objects as vararg style parameters (since rows() has an Object[] variant)
     println sql.rows("select * from PROJECT where name=?1.baz and id=?2.num", new MyDomainClass(), [num:30])

     // an example showing the model objects (one domain class and one map) provided in a list
     sql.eachRow("select * from PROJECT where name=?1.baz and id=?2.num", [new MyDomainClass(), [num:30]]) {
         // do something with row
     }

#### More details

See the method and constructor JavaDoc for more details.

For advanced usage, the class provides numerous extension points for overriding the facade behavior associated with the various aspects of managing the interaction with the underlying database.

This class is not thread-safe.

- ## Nested Class Summary

  Nested Classes
  Modifier and Type
  Class
  Description
  `protected class`
  `Sql.AbstractQueryCommand`

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `static final int`
  `ALL_RESULT_SETS`
  `static final OutParameter`
  `ARRAY`
  `static final OutParameter`
  `BIGINT`
  `static final OutParameter`
  `BINARY`
  `static final OutParameter`
  `BIT`
  `static final OutParameter`
  `BLOB`
  `static final OutParameter`
  `BOOLEAN`
  `static final OutParameter`
  `CHAR`
  `static final OutParameter`
  `CLOB`
  `static final OutParameter`
  `DATALINK`
  `static final OutParameter`
  `DATE`
  `static final OutParameter`
  `DECIMAL`
  `static final OutParameter`
  `DISTINCT`
  `static final OutParameter`
  `DOUBLE`
  `static final int`
  `FIRST_RESULT_SET`
  `static final OutParameter`
  `FLOAT`
  `static final OutParameter`
  `INTEGER`
  `static final OutParameter`
  `JAVA_OBJECT`
  `protected static final Logger`
  `LOG`
  Hook to allow derived classes to access the log
  `static final OutParameter`
  `LONGVARBINARY`
  `static final OutParameter`
  `LONGVARCHAR`
  `static final int`
  `NO_RESULT_SETS`
  `static final OutParameter`
  `NULL`
  `static final OutParameter`
  `NUMERIC`
  `static final OutParameter`
  `OTHER`
  `static final OutParameter`
  `REAL`
  `static final OutParameter`
  `REF`
  `static final OutParameter`
  `SMALLINT`
  `static final OutParameter`
  `STRUCT`
  `static final OutParameter`
  `TIME`
  `static final OutParameter`
  `TIMESTAMP`
  `static final OutParameter`
  `TINYINT`
  `static final OutParameter`
  `VARBINARY`
  `static final OutParameter`
  `VARCHAR`

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `Sql(Sql parent)`
  `Sql(Connection connection)`
  Constructs an SQL instance using the given Connection.
  `Sql(DataSource dataSource)`
  Constructs an SQL instance using the given DataSource.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `static InParameter`
  `ARRAY(Object value)`
  `protected List<GroovyRowResult>`
  `asList(String sql, ResultSet rs)`
  Hook to allow derived classes to override list of result collection behavior.
  `protected List<GroovyRowResult>`
  `asList(String sql, ResultSet rs, int offset, int maxRows, Closure metaClosure)`
  `protected List<GroovyRowResult>`
  `asList(String sql, ResultSet rs, Closure metaClosure)`
  Hook to allow derived classes to override list of result collection behavior.
  `protected String`
  `asSql(GString gstring, List<Object> values)`
  Hook to allow derived classes to override sql generation from GStrings.
  `static InParameter`
  `BIGINT(Object value)`
  `static InParameter`
  `BINARY(Object value)`
  `static InParameter`
  `BIT(Object value)`
  `static InParameter`
  `BLOB(Object value)`
  `static InParameter`
  `BOOLEAN(Object value)`
  `protected SqlWithParams`
  `buildSqlWithIndexedProps(String sql)`
  Hook to allow derived classes to override behavior associated with the parsing and indexing of parameters from a given sql statement.
  `void`
  `cacheConnection(Closure closure)`
  Caches the connection used while the closure is active.
  `void`
  `cacheStatements(Closure closure)`
  Caches every created preparedStatement in Closure closure Every cached preparedStatement is closed after closure has been called.
  `int`
  `call(GString gstring)`
  Performs a stored procedure call with the given embedded parameters.
  `void`
  `call(GString gstring, Closure closure)`
  Performs a stored procedure call with the given parameters, calling the closure once with all result objects.
  `int`
  `call(String sql)`
  Performs a stored procedure call.
  `int`
  `call(String sql, Object[] params)`
  Performs a stored procedure call with the given parameters.
  `int`
  `call(String sql, List<Object> params)`
  Performs a stored procedure call with the given parameters.
  `void`
  `call(String sql, List<Object> params, Closure closure)`
  Performs a stored procedure call with the given parameters.
  `List<List<GroovyRowResult>>`
  `callWithAllRows(GString gstring, Closure closure)`
  Performs a stored procedure call with the given parameters, calling the closure once with all result objects, and also returning a list of lists with the rows of the ResultSet(s).
  `List<List<GroovyRowResult>>`
  `callWithAllRows(String sql, List<Object> params, Closure closure)`
  Performs a stored procedure call with the given parameters, calling the closure once with all result objects, and also returning a list of lists with the rows of the ResultSet(s).
  `List<GroovyRowResult>`
  `callWithRows(GString gstring, Closure closure)`
  Performs a stored procedure call with the given parameters, calling the closure once with all result objects, and also returning the rows of the ResultSet.
  `protected List<List<GroovyRowResult>>`
  `callWithRows(String sql, List<Object> params, int processResultsSets, Closure closure)`
  Base internal method for call(), callWithRows(), and callWithAllRows() style of methods.
  `List<GroovyRowResult>`
  `callWithRows(String sql, List<Object> params, Closure closure)`
  Performs a stored procedure call with the given parameters, calling the closure once with all result objects, and also returning the rows of the ResultSet.
  `static InParameter`
  `CHAR(Object value)`
  `SqlWithParams`
  `checkForNamedParams(String sql, List<Object> params)`
  `protected void`
  `cleanup(Statement statement)`
  Provides a hook for derived classes to be able to examine JDBC statements before cleanup/closing.
  `static InParameter`
  `CLOB(Object value)`
  `void`
  `close()`
  If this SQL object was created with a Connection then this method closes the connection.
  `protected void`
  `closeResources(Connection connection)`
  An extension point allowing the behavior of resource closing to be overridden in derived classes.
  `protected void`
  `closeResources(Connection connection, Statement statement)`
  An extension point allowing the behavior of resource closing to be overridden in derived classes.
  `protected void`
  `closeResources(Connection connection, Statement statement, ResultSet results)`
  An extension point allowing derived classes to change the behavior of resource closing.
  `void`
  `commit()`
  If this SQL object was created with a Connection then this method commits the connection.
  `protected void`
  `configure(Statement statement)`
  Provides a hook for derived classes to be able to configure JDBC statements.
  `protected Connection`
  `createConnection()`
  An extension point allowing derived classes to change the behavior of connection creation.
  `protected Sql.AbstractQueryCommand`
  `createPreparedQueryCommand(String sql, List<Object> queryParams)`
  Factory for the PreparedQueryCommand command pattern object allows subclass to supply implementations of the command class.
  `protected Sql.AbstractQueryCommand`
  `createQueryCommand(String sql)`
  Factory for the QueryCommand command pattern object allows subclasses to supply implementations of the command class.
  `static InParameter`
  `DATALINK(Object value)`
  `DataSet`
  `dataSet(Class<?> type)`
  `DataSet`
  `dataSet(String table)`
  `static InParameter`
  `DATE(Object value)`
  `static InParameter`
  `DECIMAL(Object value)`
  `static InParameter`
  `DISTINCT(Object value)`
  `static InParameter`
  `DOUBLE(Object value)`
  `void`
  `eachRow(GString gstring, int offset, int maxRows, Closure closure)`
  Performs the given SQL query calling the given `closure` with each row of the result set starting at the provided `offset`, and including up to `maxRows` number of rows.
  `void`
  `eachRow(GString gstring, Closure closure)`
  Performs the given SQL query calling the given Closure with each row of the result set.
  `void`
  `eachRow(GString gstring, Closure metaClosure, int offset, int maxRows, Closure rowClosure)`
  Performs the given SQL query calling the given `closure` with each row of the result set starting at the provided `offset`, and including up to `maxRows` number of rows.
  `void`
  `eachRow(GString gstring, Closure metaClosure, Closure rowClosure)`
  Performs the given SQL query calling the given Closure with each row of the result set.
  `void`
  `eachRow(String sql, int offset, int maxRows, Closure closure)`
  Performs the given SQL query calling the given `closure` with each row of the result set starting at the provided `offset`, and including up to `maxRows` number of rows.
  `void`
  `eachRow(String sql, Closure closure)`
  Performs the given SQL query calling the given Closure with each row of the result set.
  `void`
  `eachRow(String sql, Closure metaClosure, int offset, int maxRows, Closure rowClosure)`
  Performs the given SQL query calling the given `rowClosure` with each row of the result set starting at the provided `offset`, and including up to `maxRows` number of rows.
  `void`
  `eachRow(String sql, Closure metaClosure, Closure rowClosure)`
  Performs the given SQL query calling the given `rowClosure` with each row of the result set.
  `void`
  `eachRow(String sql, List<Object> params, int offset, int maxRows, Closure closure)`
  Performs the given SQL query calling the given `closure` with each row of the result set starting at the provided `offset`, and including up to `maxRows` number of rows.
  `void`
  `eachRow(String sql, List<Object> params, Closure closure)`
  Performs the given SQL query calling the given Closure with each row of the result set.
  `void`
  `eachRow(String sql, List<Object> params, Closure metaClosure, int offset, int maxRows, Closure rowClosure)`
  Performs the given SQL query calling the given `rowClosure` with each row of the result set starting at the provided `offset`, and including up to `maxRows` number of rows.
  `void`
  `eachRow(String sql, List<Object> params, Closure metaClosure, Closure rowClosure)`
  Performs the given SQL query calling the given Closure with each row of the result set.
  `void`
  `eachRow(String sql, Map params, int offset, int maxRows, Closure closure)`
  A variant of `eachRow(String, java.util.List, int, int, groovy.lang.Closure)` useful when providing the named parameters as a map.
  `void`
  `eachRow(String sql, Map params, Closure closure)`
  A variant of `eachRow(String, java.util.List, groovy.lang.Closure)` useful when providing the named parameters as a map.
  `void`
  `eachRow(String sql, Map map, Closure metaClosure, int offset, int maxRows, Closure rowClosure)`
  A variant of `eachRow(String, java.util.List, groovy.lang.Closure, int, int, groovy.lang.Closure)` allowing the named parameters to be supplied in a map.
  `void`
  `eachRow(String sql, Map params, Closure metaClosure, Closure rowClosure)`
  A variant of `eachRow(String, java.util.List, groovy.lang.Closure, groovy.lang.Closure)` useful when providing the named parameters as a map.
  `void`
  `eachRow(Map params, String sql, int offset, int maxRows, Closure closure)`
  A variant of `eachRow(String, java.util.List, int, int, groovy.lang.Closure)` useful when providing the named parameters as named arguments.
  `void`
  `eachRow(Map params, String sql, Closure closure)`
  A variant of `eachRow(String, java.util.List, groovy.lang.Closure)` useful when providing the named parameters as named arguments.
  `void`
  `eachRow(Map map, String sql, Closure metaClosure, int offset, int maxRows, Closure rowClosure)`
  A variant of `eachRow(String, java.util.List, groovy.lang.Closure, int, int, groovy.lang.Closure)` allowing the named parameters to be supplied as named arguments.
  `void`
  `eachRow(Map params, String sql, Closure metaClosure, Closure rowClosure)`
  A variant of `eachRow(String, java.util.List, groovy.lang.Closure, groovy.lang.Closure)` useful when providing the named parameters as named arguments.
  `boolean`
  `execute(GString gstring)`
  Executes the given SQL with embedded expressions inside.
  `void`
  `execute(GString gstring, Closure processResults)`
  Executes the given SQL with embedded expressions inside.
  `boolean`
  `execute(String sql)`
  Executes the given piece of SQL.
  `void`
  `execute(String sql, Closure processResults)`
  Executes the given piece of SQL.
  `boolean`
  `execute(String sql, Object[] params)`
  Executes the given piece of SQL with parameters.
  `void`
  `execute(String sql, Object[] params, Closure processResults)`
  Executes the given piece of SQL with parameters.
  `boolean`
  `execute(String sql, List<Object> params)`
  Executes the given piece of SQL with parameters.
  `void`
  `execute(String sql, List<Object> params, Closure processResults)`
  Executes the given piece of SQL with parameters.
  `boolean`
  `execute(Map params, String sql)`
  A variant of `execute(String, java.util.List)` useful when providing the named parameters as named arguments.
  `void`
  `execute(Map params, String sql, Closure processResults)`
  A variant of `execute(String, java.util.List, Closure)` useful when providing the named parameters as named arguments.
  `List<List<Object>>`
  `executeInsert(GString gstring)`
  Executes the given SQL statement (typically an INSERT statement).
  `List<GroovyRowResult>`
  `executeInsert(GString gstring, List<String> keyColumnNames)`
  Executes the given SQL statement (typically an INSERT statement).
  `List<List<Object>>`
  `executeInsert(String sql)`
  Executes the given SQL statement (typically an INSERT statement).
  `List<List<Object>>`
  `executeInsert(String sql, Object[] params)`
  Executes the given SQL statement (typically an INSERT statement).
  `List<GroovyRowResult>`
  `executeInsert(String sql, String[] keyColumnNames)`
  Executes the given SQL statement (typically an INSERT statement).
  `List<GroovyRowResult>`
  `executeInsert(String sql, String[] keyColumnNames, Object[] params)`
  Executes the given SQL statement (typically an INSERT statement).
  `List<List<Object>>`
  `executeInsert(String sql, List<Object> params)`
  Executes the given SQL statement (typically an INSERT statement).
  `List<GroovyRowResult>`
  `executeInsert(String sql, List<Object> params, List<String> keyColumnNames)`
  Executes the given SQL statement (typically an INSERT statement).
  `List<List<Object>>`
  `executeInsert(Map params, String sql)`
  A variant of `executeInsert(String, java.util.List)` useful when providing the named parameters as named arguments.
  `List<GroovyRowResult>`
  `executeInsert(Map params, String sql, List<String> keyColumnNames)`
  A variant of `executeInsert(String, List, List)` useful when providing the named parameters as named arguments.
  `protected final ResultSet`
  `executePreparedQuery(String sql, List<Object> params)`
  Useful helper method which handles resource management when executing a prepared query which returns a result set.
  `protected final ResultSet`
  `executeQuery(String sql)`
  Useful helper method which handles resource management when executing a query which returns a result set.
  `int`
  `executeUpdate(GString gstring)`
  Executes the given SQL update with embedded expressions inside.
  `int`
  `executeUpdate(String sql)`
  Executes the given SQL update.
  `int`
  `executeUpdate(String sql, Object[] params)`
  Executes the given SQL update with parameters.
  `int`
  `executeUpdate(String sql, List<Object> params)`
  Executes the given SQL update with parameters.
  `int`
  `executeUpdate(Map params, String sql)`
  A variant of `executeUpdate(String, java.util.List)` useful when providing the named parameters as named arguments.
  `static ExpandedVariable`
  `expand(Object object)`
  When using GString SQL queries, allows a variable to be expanded in the Sql string rather than representing an sql parameter.
  `protected int`
  `findWhereKeyword(String sql)`
  Hook to allow derived classes to override where clause sniffing.
  `GroovyRowResult`
  `firstRow(GString gstring)`
  Performs the given SQL query and return the first row of the result set.
  `GroovyRowResult`
  `firstRow(String sql)`
  Performs the given SQL query and return the first row of the result set.
  `GroovyRowResult`
  `firstRow(String sql, Object[] params)`
  Performs the given SQL query and return the first row of the result set.
  `GroovyRowResult`
  `firstRow(String sql, List<Object> params)`
  Performs the given SQL query and return the first row of the result set.
  `GroovyRowResult`
  `firstRow(Map params, String sql)`
  A variant of `firstRow(String, java.util.List)` useful when providing the named parameters as named arguments.
  `static InParameter`
  `FLOAT(Object value)`
  `Connection`
  `getConnection()`
  If this instance was created with a single Connection then the connection is returned.
  `DataSource`
  `getDataSource()`
  `protected List<Object>`
  `getParameters(GString gstring)`
  Hook to allow derived classes to override behavior associated with extracting params from a GString.
  `int`
  `getResultSetConcurrency()`
  Gets the resultSetConcurrency for statements created using the connection.
  `int`
  `getResultSetHoldability()`
  Gets the resultSetHoldability for statements created using the connection.
  `int`
  `getResultSetType()`
  Gets the resultSetType for statements created using the connection.
  `int`
  `getUpdateCount()`
  `List<Object>`
  `getUpdatedParams(List<Object> params, List<Tuple> indexPropList)`
  `static InParameter`
  `in(int type, Object value)`
  Create a new InParameter
  `static InOutParameter`
  `inout(InParameter in)`
  Create an inout parameter using this in parameter.
  `static InParameter`
  `INTEGER(Object value)`
  `boolean`
  `isCacheNamedQueries()`
  `boolean`
  `isCacheStatements()`
  `boolean`
  `isEnableNamedQueries()`
  `boolean`
  `isWithinBatch()`
  Returns true if the current Sql object is currently executing a withBatch method call.
  `static InParameter`
  `JAVA_OBJECT(Object value)`
  `static void`
  `loadDriver(String driverClassName)`
  Attempts to load the JDBC driver on the thread, current or system class loaders
  `static InParameter`
  `LONGVARBINARY(Object value)`
  `static InParameter`
  `LONGVARCHAR(Object value)`
  `static Sql`
  `newInstance(String url)`
  Creates a new Sql instance given a JDBC connection URL.
  `static Sql`
  `newInstance(String url, String driverClassName)`
  Creates a new Sql instance given a JDBC connection URL and a driver class name.
  `static Sql`
  `newInstance(String url, String user, String password)`
  Creates a new Sql instance given a JDBC connection URL, a username and a password.
  `static Sql`
  `newInstance(String url, String user, String password, String driverClassName)`
  Creates a new Sql instance given a JDBC connection URL, a username, a password and a driver class name.
  `static Sql`
  `newInstance(String url, Properties properties)`
  Creates a new Sql instance given a JDBC connection URL and some properties.
  `static Sql`
  `newInstance(String url, Properties properties, String driverClassName)`
  Creates a new Sql instance given a JDBC connection URL, some properties and a driver class name.
  `static Sql`
  `newInstance(Map<String,Object> args)`
  Creates a new Sql instance given parameters in a Map.
  `static InParameter`
  `NULL(Object value)`
  `protected String`
  `nullify(String sql)`
  Hook to allow derived classes to override null handling.
  `static InParameter`
  `NUMERIC(Object value)`
  `static InParameter`
  `OTHER(Object value)`
  `static OutParameter`
  `out(int type)`
  Create a new OutParameter
  `SqlWithParams`
  `preCheckForNamedParams(String sql)`
  Deprecated.
  Use `buildSqlWithIndexedProps(String)` instead
  `void`
  `query(GString gstring, Closure closure)`
  Performs the given SQL query, which should return a single `ResultSet` object.
  `void`
  `query(String sql, Closure closure)`
  Performs the given SQL query, which should return a single `ResultSet` object.
  `void`
  `query(String sql, List<Object> params, Closure closure)`
  Performs the given SQL query, which should return a single `ResultSet` object.
  `void`
  `query(String sql, Map map, Closure closure)`
  A variant of `query(String, java.util.List, groovy.lang.Closure)` useful when providing the named parameters as a map.
  `void`
  `query(Map map, String sql, Closure closure)`
  A variant of `query(String, java.util.List, groovy.lang.Closure)` useful when providing the named parameters as named arguments.
  `static InParameter`
  `REAL(Object value)`
  `static InParameter`
  `REF(Object value)`
  `static ResultSetOutParameter`
  `resultSet(int type)`
  Create a new ResultSetOutParameter
  `void`
  `rollback()`
  If this SQL object was created with a Connection then this method rolls back the connection.
  `List<GroovyRowResult>`
  `rows(GString gstring)`
  Performs the given SQL query and return the rows of the result set.
  `List<GroovyRowResult>`
  `rows(GString sql, int offset, int maxRows)`
  Performs the given SQL query and return a "page" of rows from the result set.
  `List<GroovyRowResult>`
  `rows(GString gstring, int offset, int maxRows, Closure metaClosure)`
  Performs the given SQL query and return a "page" of rows from the result set.
  `List<GroovyRowResult>`
  `rows(GString gstring, Closure metaClosure)`
  Performs the given SQL query and return the rows of the result set.
  `List<GroovyRowResult>`
  `rows(String sql)`
  Performs the given SQL query and return the rows of the result set.
  `List<GroovyRowResult>`
  `rows(String sql, int offset, int maxRows)`
  Performs the given SQL query and return a "page" of rows from the result set.
  `List<GroovyRowResult>`
  `rows(String sql, int offset, int maxRows, Closure metaClosure)`
  Performs the given SQL query and return a "page" of rows from the result set.
  `List<GroovyRowResult>`
  `rows(String sql, Closure metaClosure)`
  Performs the given SQL query and return the rows of the result set.
  `List<GroovyRowResult>`
  `rows(String sql, Object[] params)`
  Performs the given SQL query and return the rows of the result set.
  `List<GroovyRowResult>`
  `rows(String sql, Object[] params, int offset, int maxRows)`
  Performs the given SQL query and return the rows of the result set.
  `List<GroovyRowResult>`
  `rows(String sql, List<Object> params)`
  Performs the given SQL query and return the rows of the result set.
  `List<GroovyRowResult>`
  `rows(String sql, List<Object> params, int offset, int maxRows)`
  Performs the given SQL query and return a "page" of rows from the result set.
  `List<GroovyRowResult>`
  `rows(String sql, List<Object> params, int offset, int maxRows, Closure metaClosure)`
  Performs the given SQL query and return a "page" of rows from the result set.
  `List<GroovyRowResult>`
  `rows(String sql, List<Object> params, Closure metaClosure)`
  Performs the given SQL query and return the rows of the result set.
  `List<GroovyRowResult>`
  `rows(String sql, Map params, int offset, int maxRows)`
  A variant of `rows(String, java.util.List, int, int)` useful when providing the named parameters as a map.
  `List<GroovyRowResult>`
  `rows(String sql, Map params, int offset, int maxRows, Closure metaClosure)`
  A variant of `rows(String, java.util.List, int, int, groovy.lang.Closure)` useful when providing the named parameters as a map.
  `List<GroovyRowResult>`
  `rows(String sql, Map params, Closure metaClosure)`
  A variant of `rows(String, java.util.List, groovy.lang.Closure)` useful when providing the named parameters as a map.
  `List<GroovyRowResult>`
  `rows(Map params, String sql)`
  A variant of `rows(String, java.util.List)` useful when providing the named parameters as named arguments.
  `List<GroovyRowResult>`
  `rows(Map params, String sql, int offset, int maxRows)`
  A variant of `rows(String, java.util.List, int, int)` useful when providing the named parameters as named arguments.
  `List<GroovyRowResult>`
  `rows(Map params, String sql, int offset, int maxRows, Closure metaClosure)`
  A variant of `rows(String, java.util.List, int, int, groovy.lang.Closure)` useful when providing the named parameters as named arguments.
  `List<GroovyRowResult>`
  `rows(Map params, String sql, Closure metaClosure)`
  A variant of `rows(String, java.util.List, groovy.lang.Closure)` useful when providing the named parameters as named arguments.
  `void`
  `setCacheNamedQueries(boolean cacheNamedQueries)`
  Enables named query caching.
  if cacheNamedQueries is true, cache is created and processed named queries will be cached.
  `void`
  `setCacheStatements(boolean cacheStatements)`
  Enables statement caching.
  if cacheStatements is true, cache is created and all created prepared statements will be cached.
  `void`
  `setEnableNamedQueries(boolean enableNamedQueries)`
  Enables named query support: if enableNamedQueries is true, queries with ':propname' and '?1.propname' style placeholders will be processed. if enableNamedQueries is false, this feature will be turned off.
  `protected void`
  `setInternalConnection(Connection conn)`
  Stub needed for testing.
  `protected void`
  `setObject(PreparedStatement statement, int i, Object value)`
  Strategy method allowing derived classes to handle types differently such as for CLOBs etc.
  `protected void`
  `setParameters(List<Object> params, PreparedStatement statement)`
  Hook to allow derived classes to override behavior associated with setting params for a prepared statement.
  `void`
  `setResultSetConcurrency(int resultSetConcurrency)`
  Sets the resultSetConcurrency for statements created using the connection.
  `void`
  `setResultSetHoldability(int resultSetHoldability)`
  Sets the resultSetHoldability for statements created using the connection.
  `void`
  `setResultSetType(int resultSetType)`
  Sets the resultSetType for statements created using the connection.
  `static InParameter`
  `SMALLINT(Object value)`
  `static InParameter`
  `STRUCT(Object value)`
  `static InParameter`
  `TIME(Object value)`
  `static InParameter`
  `TIMESTAMP(Object value)`
  `static InParameter`
  `TINYINT(Object value)`
  `static InParameter`
  `VARBINARY(Object value)`
  `static InParameter`
  `VARCHAR(Object value)`
  `int[]`
  `withBatch(int batchSize, Closure closure)`
  Performs the closure (containing batch operations) within a batch using a given batch size.
  `int[]`
  `withBatch(int batchSize, String sql, Closure closure)`
  Performs the closure (containing batch operations specific to an associated prepared statement) within a batch using a given batch size.
  `int[]`
  `withBatch(Closure closure)`
  Performs the closure (containing batch operations) within a batch.
  `int[]`
  `withBatch(String sql, Closure closure)`
  Performs the closure (containing batch operations specific to an associated prepared statement) within a batch.
  `void`
  `withCleanupStatement(Closure cleanupStatement)`
  Allows a closure to be passed in which acts as a hook for JDBC statements before they are closed.
  `static void`
  `withInstance(String url, Closure c)`
  Invokes a closure passing it a new Sql instance created from the given JDBC connection URL.
  `static void`
  `withInstance(String url, String driverClassName, Closure c)`
  Invokes a closure passing it a new Sql instance created from the given JDBC connection URL.
  `static void`
  `withInstance(String url, String user, String password, Closure c)`
  Invokes a closure passing it a new Sql instance created from the given JDBC connection URL, user and password.
  `static void`
  `withInstance(String url, String user, String password, String driverClassName, Closure c)`
  Invokes a closure passing it a new Sql instance created from the given JDBC connection URL.
  `static void`
  `withInstance(String url, Properties properties, Closure c)`
  Invokes a closure passing it a new Sql instance created from the given JDBC connection URL and properties.
  `static void`
  `withInstance(String url, Properties properties, String driverClassName, Closure c)`
  Invokes a closure passing it a new Sql instance created from the given JDBC connection URL, properties and driver classname.
  `static void`
  `withInstance(Map<String,Object> args, Closure c)`
  Invokes a closure passing it a new Sql instance created from the given map of arguments.
  `void`
  `withStatement(Closure configureStatement)`
  Allows a closure to be passed in to configure the JDBC statements before they are executed.
  `void`
  `withTransaction(Closure closure)`
  Performs the closure within a transaction using a cached connection.

  ### Methods inherited from class java.lang.Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- ## Field Details

  - ### LOG

    protected static final Logger LOG
    Hook to allow derived classes to access the log

  - ### ARRAY

    public static final OutParameter ARRAY

  - ### BIGINT

    public static final OutParameter BIGINT

  - ### BINARY

    public static final OutParameter BINARY

  - ### BIT

    public static final OutParameter BIT

  - ### BLOB

    public static final OutParameter BLOB

  - ### BOOLEAN

    public static final OutParameter BOOLEAN

  - ### CHAR

    public static final OutParameter CHAR

  - ### CLOB

    public static final OutParameter CLOB

  - ### DATALINK

    public static final OutParameter DATALINK

  - ### DATE

    public static final OutParameter DATE

  - ### DECIMAL

    public static final OutParameter DECIMAL

  - ### DISTINCT

    public static final OutParameter DISTINCT

  - ### DOUBLE

    public static final OutParameter DOUBLE

  - ### FLOAT

    public static final OutParameter FLOAT

  - ### INTEGER

    public static final OutParameter INTEGER

  - ### JAVA_OBJECT

    public static final OutParameter JAVA_OBJECT

  - ### LONGVARBINARY

    public static final OutParameter LONGVARBINARY

  - ### LONGVARCHAR

    public static final OutParameter LONGVARCHAR

  - ### NULL

    public static final OutParameter NULL

  - ### NUMERIC

    public static final OutParameter NUMERIC

  - ### OTHER

    public static final OutParameter OTHER

  - ### REAL

    public static final OutParameter REAL

  - ### REF

    public static final OutParameter REF

  - ### SMALLINT

    public static final OutParameter SMALLINT

  - ### STRUCT

    public static final OutParameter STRUCT

  - ### TIME

    public static final OutParameter TIME

  - ### TIMESTAMP

    public static final OutParameter TIMESTAMP

  - ### TINYINT

    public static final OutParameter TINYINT

  - ### VARBINARY

    public static final OutParameter VARBINARY

  - ### VARCHAR

    public static final OutParameter VARCHAR

  - ### NO_RESULT_SETS

    public static final int NO_RESULT_SETS
    See Also:
      - Constant Field Values

  - ### FIRST_RESULT_SET

    public static final int FIRST_RESULT_SET
    See Also:
      - Constant Field Values

  - ### ALL_RESULT_SETS

    public static final int ALL_RESULT_SETS
    See Also:
      - Constant Field Values

- ## Constructor Details

  - ### Sql

    public Sql(DataSource dataSource)
    Constructs an SQL instance using the given DataSource. Each operation will use a Connection from the DataSource pool and close it when the operation is completed putting it back into the pool.
    Parameters:
      `dataSource` - the DataSource to use

  - ### Sql

    public Sql(Connection connection)
    Constructs an SQL instance using the given Connection. It is the caller's responsibility to close the Connection after the Sql instance has been used. Depending on which features you are using, you may be able to do this on the connection object directly but the preferred approach is to call the `close()` method which will close the connection but also free any cached resources.
    Parameters:
      `connection` - the Connection to use

  - ### Sql

    public Sql(Sql parent)

- ## Method Details

  - ### newInstance

    public static Sql newInstance(String url) throws SQLException
    Creates a new Sql instance given a JDBC connection URL.
    Parameters:
      `url` - a database url of the form `jdbc:subprotocol:subname`
    Returns:
      a new Sql instance with a connection
    Throws:
      `SQLException` - if a database access error occurs

  - ### withInstance

    public static void withInstance(String url, Closure c) throws SQLException
    Invokes a closure passing it a new Sql instance created from the given JDBC connection URL. The created connection will be closed if required.
    Parameters:
      `url` - a database url of the form `jdbc:subprotocol:subname`
      `c` - the Closure to call
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `newInstance(String)`

  - ### newInstance

    public static Sql newInstance(String url, Properties properties) throws SQLException
    Creates a new Sql instance given a JDBC connection URL and some properties.
    Parameters:
      `url` - a database url of the form `jdbc:subprotocol:subname`
      `properties` - a list of arbitrary string tag/value pairs as connection arguments; normally at least a "user" and "password" property should be included
    Returns:
      a new Sql instance with a connection
    Throws:
      `SQLException` - if a database access error occurs

  - ### withInstance

    public static void withInstance(String url, Properties properties, Closure c) throws SQLException
    Invokes a closure passing it a new Sql instance created from the given JDBC connection URL and properties. The created connection will be closed if required.
    Parameters:
      `url` - a database url of the form `jdbc:subprotocol:subname`
      `properties` - a list of arbitrary string tag/value pairs as connection arguments; normally at least a "user" and "password" property should be included
      `c` - the Closure to call
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `newInstance(String, java.util.Properties)`

  - ### newInstance

    public static Sql newInstance(String url, Properties properties, String driverClassName) throws SQLException, ClassNotFoundException
    Creates a new Sql instance given a JDBC connection URL, some properties and a driver class name.
    Parameters:
      `url` - a database url of the form `jdbc:subprotocol:subname`
      `properties` - a list of arbitrary string tag/value pairs as connection arguments; normally at least a "user" and "password" property should be included
      `driverClassName` - the fully qualified class name of the driver class
    Returns:
      a new Sql instance with a connection
    Throws:
      `SQLException` - if a database access error occurs
      `ClassNotFoundException` - if the driver class cannot be found or loaded

  - ### withInstance

    public static void withInstance(String url, Properties properties, String driverClassName, Closure c) throws SQLException, ClassNotFoundException
    Invokes a closure passing it a new Sql instance created from the given JDBC connection URL, properties and driver classname. The created connection will be closed if required.
    Parameters:
      `url` - a database url of the form `jdbc:subprotocol:subname`
      `properties` - a list of arbitrary string tag/value pairs as connection arguments; normally at least a "user" and "password" property should be included
      `driverClassName` - the fully qualified class name of the driver class
      `c` - the Closure to call
    Throws:
      `SQLException` - if a database access error occurs
      `ClassNotFoundException` - if the driver class cannot be found or loaded
    See Also:
      - `newInstance(String, java.util.Properties, String)`

  - ### newInstance

    public static Sql newInstance(String url, String user, String password) throws SQLException
    Creates a new Sql instance given a JDBC connection URL, a username and a password.
    Parameters:
      `url` - a database url of the form `jdbc:subprotocol:subname`
      `user` - the database user on whose behalf the connection is being made
      `password` - the user's password
    Returns:
      a new Sql instance with a connection
    Throws:
      `SQLException` - if a database access error occurs

  - ### withInstance

    public static void withInstance(String url, String user, String password, Closure c) throws SQLException
    Invokes a closure passing it a new Sql instance created from the given JDBC connection URL, user and password. The created connection will be closed if required.
    Parameters:
      `url` - a database url of the form `jdbc:subprotocol:subname`
      `user` - the database user on whose behalf the connection is being made
      `password` - the user's password
      `c` - the Closure to call
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `newInstance(String, String, String)`

  - ### newInstance

    public static Sql newInstance(String url, String user, String password, String driverClassName) throws SQLException, ClassNotFoundException
    Creates a new Sql instance given a JDBC connection URL, a username, a password and a driver class name.
    Parameters:
      `url` - a database url of the form `jdbc:subprotocol:subname`
      `user` - the database user on whose behalf the connection is being made
      `password` - the user's password
      `driverClassName` - the fully qualified class name of the driver class
    Returns:
      a new Sql instance with a connection
    Throws:
      `SQLException` - if a database access error occurs
      `ClassNotFoundException` - if the driver class cannot be found or loaded

  - ### withInstance

    public static void withInstance(String url, String user, String password, String driverClassName, Closure c) throws SQLException, ClassNotFoundException
    Invokes a closure passing it a new Sql instance created from the given JDBC connection URL. The created connection will be closed if required.
    Parameters:
      `url` - a database url of the form `jdbc:subprotocol:subname`
      `user` - the database user on whose behalf the connection is being made
      `password` - the user's password
      `driverClassName` - the fully qualified class name of the driver class
      `c` - the Closure to call
    Throws:
      `SQLException` - if a database access error occurs
      `ClassNotFoundException` - if the driver class cannot be found or loaded
    See Also:
      - `newInstance(String, String, String, String)`

  - ### newInstance

    public static Sql newInstance(String url, String driverClassName) throws SQLException, ClassNotFoundException
    Creates a new Sql instance given a JDBC connection URL and a driver class name.
    Parameters:
      `url` - a database url of the form `jdbc:subprotocol:subname`
      `driverClassName` - the fully qualified class name of the driver class
    Returns:
      a new Sql instance with a connection
    Throws:
      `SQLException` - if a database access error occurs
      `ClassNotFoundException` - if the driver class cannot be found or loaded

  - ### withInstance

    public static void withInstance(String url, String driverClassName, Closure c) throws SQLException, ClassNotFoundException
    Invokes a closure passing it a new Sql instance created from the given JDBC connection URL. The created connection will be closed if required.
    Parameters:
      `url` - a database url of the form `jdbc:subprotocol:subname`
      `driverClassName` - the fully qualified class name of the driver class
      `c` - the Closure to call
    Throws:
      `SQLException` - if a database access error occurs
      `ClassNotFoundException` - if the driver class cannot be found or loaded
    See Also:
      - `newInstance(String, String)`

  - ### newInstance

    public static Sql newInstance(Map<String,Object> args) throws SQLException, ClassNotFoundException
    Creates a new Sql instance given parameters in a Map. Recognized keys for the Map include:

         driverClassName the fully qualified class name of the driver class
         driver          a synonym for driverClassName
         url             a database url of the form: jdbc:subprotocol:subname
         user            the database user on whose behalf the connection is being made
         password        the user's password
         properties      a list of arbitrary string tag/value pairs as connection arguments;
                         normally at least a "user" and "password" property should be included
         other           any of the public setter methods of this class may be used with property notation
                         e.g. cacheStatements: true, resultSetConcurrency: ResultSet.CONCUR_READ_ONLY

    Of these, '`url`' is required. Others may be needed depending on your database.
    If '`properties`' is supplied, neither '`user`' nor '`password`' should be supplied.
    If one of '`user`' or '`password`' is supplied, both should be supplied.

    Example usage:

         import groovy.sql.Sql
         import static java.sql.ResultSet.*

         def sql = Sql.newInstance(
             url:'jdbc:hsqldb:mem:testDB',
             user:'sa',
             password:'',
             driver:'org.hsqldb.jdbc.JDBCDriver',
             cacheStatements: true,
             resultSetConcurrency: CONCUR_READ_ONLY
         )

    Parameters:
      `args` - a Map contain further arguments
    Returns:
      a new Sql instance with a connection
    Throws:
      `SQLException` - if a database access error occurs
      `ClassNotFoundException` - if the driver class cannot be found or loaded

  - ### withInstance

    public static void withInstance(Map<String,Object> args, Closure c) throws SQLException, ClassNotFoundException
    Invokes a closure passing it a new Sql instance created from the given map of arguments. The created connection will be closed if required.
    Parameters:
      `args` - a Map contain further arguments
      `c` - the Closure to call
    Throws:
      `SQLException` - if a database access error occurs
      `ClassNotFoundException` - if the driver class cannot be found or loaded
    See Also:
      - `newInstance(java.util.Map)`

  - ### getResultSetType

    public int getResultSetType()
    Gets the resultSetType for statements created using the connection.
    Returns:
      the current resultSetType value
    Since:
      1.5.2

  - ### setResultSetType

    public void setResultSetType(int resultSetType)
    Sets the resultSetType for statements created using the connection. May cause SQLFeatureNotSupportedException exceptions to occur if the underlying database doesn't support the requested type value.
    Parameters:
      `resultSetType` - one of the following `ResultSet` constants: `ResultSet.TYPE_FORWARD_ONLY`, `ResultSet.TYPE_SCROLL_INSENSITIVE`, or `ResultSet.TYPE_SCROLL_SENSITIVE`
    Since:
      1.5.2

  - ### getResultSetConcurrency

    public int getResultSetConcurrency()
    Gets the resultSetConcurrency for statements created using the connection.
    Returns:
      the current resultSetConcurrency value
    Since:
      1.5.2

  - ### setResultSetConcurrency

    public void setResultSetConcurrency(int resultSetConcurrency)
    Sets the resultSetConcurrency for statements created using the connection. May cause SQLFeatureNotSupportedException exceptions to occur if the underlying database doesn't support the requested concurrency value.
    Parameters:
      `resultSetConcurrency` - one of the following `ResultSet` constants: `ResultSet.CONCUR_READ_ONLY` or `ResultSet.CONCUR_UPDATABLE`
    Since:
      1.5.2

  - ### getResultSetHoldability

    public int getResultSetHoldability()
    Gets the resultSetHoldability for statements created using the connection.
    Returns:
      the current resultSetHoldability value or -1 if not set
    Since:
      1.5.2

  - ### setResultSetHoldability

    public void setResultSetHoldability(int resultSetHoldability)
    Sets the resultSetHoldability for statements created using the connection. May cause SQLFeatureNotSupportedException exceptions to occur if the underlying database doesn't support the requested holdability value.
    Parameters:
      `resultSetHoldability` - one of the following `ResultSet` constants: `ResultSet.HOLD_CURSORS_OVER_COMMIT` or `ResultSet.CLOSE_CURSORS_AT_COMMIT`
    Since:
      1.5.2

  - ### loadDriver

    public static void loadDriver(String driverClassName) throws ClassNotFoundException
    Attempts to load the JDBC driver on the thread, current or system class loaders
    Parameters:
      `driverClassName` - the fully qualified class name of the driver class
    Throws:
      `ClassNotFoundException` - if the class cannot be found or loaded

  - ### ARRAY

    public static InParameter ARRAY(Object value)

  - ### BIGINT

    public static InParameter BIGINT(Object value)

  - ### BINARY

    public static InParameter BINARY(Object value)

  - ### BIT

    public static InParameter BIT(Object value)

  - ### BLOB

    public static InParameter BLOB(Object value)

  - ### BOOLEAN

    public static InParameter BOOLEAN(Object value)

  - ### CHAR

    public static InParameter CHAR(Object value)

  - ### CLOB

    public static InParameter CLOB(Object value)

  - ### DATALINK

    public static InParameter DATALINK(Object value)

  - ### DATE

    public static InParameter DATE(Object value)

  - ### DECIMAL

    public static InParameter DECIMAL(Object value)

  - ### DISTINCT

    public static InParameter DISTINCT(Object value)

  - ### DOUBLE

    public static InParameter DOUBLE(Object value)

  - ### FLOAT

    public static InParameter FLOAT(Object value)

  - ### INTEGER

    public static InParameter INTEGER(Object value)

  - ### JAVA_OBJECT

    public static InParameter JAVA_OBJECT(Object value)

  - ### LONGVARBINARY

    public static InParameter LONGVARBINARY(Object value)

  - ### LONGVARCHAR

    public static InParameter LONGVARCHAR(Object value)

  - ### NULL

    public static InParameter NULL(Object value)

  - ### NUMERIC

    public static InParameter NUMERIC(Object value)

  - ### OTHER

    public static InParameter OTHER(Object value)

  - ### REAL

    public static InParameter REAL(Object value)

  - ### REF

    public static InParameter REF(Object value)

  - ### SMALLINT

    public static InParameter SMALLINT(Object value)

  - ### STRUCT

    public static InParameter STRUCT(Object value)

  - ### TIME

    public static InParameter TIME(Object value)

  - ### TIMESTAMP

    public static InParameter TIMESTAMP(Object value)

  - ### TINYINT

    public static InParameter TINYINT(Object value)

  - ### VARBINARY

    public static InParameter VARBINARY(Object value)

  - ### VARCHAR

    public static InParameter VARCHAR(Object value)

  - ### in

    public static InParameter in(int type, Object value)
    Create a new InParameter
    Parameters:
      `type` - the JDBC data type
      `value` - the object value
    Returns:
      an InParameter

  - ### out

    public static OutParameter out(int type)
    Create a new OutParameter
    Parameters:
      `type` - the JDBC data type.
    Returns:
      an OutParameter

  - ### inout

    public static InOutParameter inout(InParameter in)
    Create an inout parameter using this in parameter.
    Parameters:
      `in` - the InParameter of interest
    Returns:
      the resulting InOutParameter

  - ### resultSet

    public static ResultSetOutParameter resultSet(int type)
    Create a new ResultSetOutParameter
    Parameters:
      `type` - the JDBC data type.
    Returns:
      a ResultSetOutParameter

  - ### expand

    public static ExpandedVariable expand(Object object)
    When using GString SQL queries, allows a variable to be expanded in the Sql string rather than representing an sql parameter.

    Example usage:

         def fieldName = 'firstname'
         def fieldOp = Sql.expand('like')
         def fieldVal = '%a%'
         sql.query "select * from PERSON where ${Sql.expand(fieldName)} $fieldOp ${fieldVal}", { ResultSet rs ->
             while (rs.next()) println rs.getString('firstname')
         }
         // query will be 'select * from PERSON where firstname like ?'
         // params will be [fieldVal]

    Parameters:
      `object` - the object of interest
    Returns:
      the expanded variable
    See Also:
      - `expand(Object)`

  - ### dataSet

    public DataSet dataSet(String table)

  - ### dataSet

    public DataSet dataSet(Class<?> type)

  - ### query

    public void query(String sql, Closure closure) throws SQLException
    Performs the given SQL query, which should return a single `ResultSet` object. The given closure is called with the `ResultSet` as its argument.

    Example usages:

         sql.query("select * from PERSON where firstname like 'S%'") { ResultSet rs ->
             while (rs.next()) println rs.getString('firstname') + ' ' + rs.getString(3)
         }

         sql.query("call get_people_places()") { ResultSet rs ->
             while (rs.next()) println rs.toRowResult().firstname
         }

    All resources including the ResultSet are closed automatically after the closure is called.

    Parameters:
      `sql` - the sql statement
      `closure` - called for each row with a `ResultSet`
    Throws:
      `SQLException` - if a database access error occurs

  - ### query

    public void query(String sql, List<Object> params, Closure closure) throws SQLException
    Performs the given SQL query, which should return a single `ResultSet` object. The given closure is called with the `ResultSet` as its argument. The query may contain placeholder question marks which match the given list of parameters.

    Example usage:

         sql.query('select * from PERSON where lastname like ?', ['%a%']) { ResultSet rs ->
             while (rs.next()) println rs.getString('lastname')
         }

    This method supports named and named ordinal parameters. See the class Javadoc for more details.

    All resources including the ResultSet are closed automatically after the closure is called.

    Parameters:
      `sql` - the sql statement
      `params` - a list of parameters
      `closure` - called for each row with a `ResultSet`
    Throws:
      `SQLException` - if a database access error occurs

  - ### query

    public void query(String sql, Map map, Closure closure) throws SQLException
    A variant of `query(String, java.util.List, groovy.lang.Closure)` useful when providing the named parameters as a map.
    Parameters:
      `sql` - the sql statement
      `map` - a map containing the named parameters
      `closure` - called for each row with a `ResultSet`
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### query

    public void query(Map map, String sql, Closure closure) throws SQLException
    A variant of `query(String, java.util.List, groovy.lang.Closure)` useful when providing the named parameters as named arguments.
    Parameters:
      `map` - a map containing the named parameters
      `sql` - the sql statement
      `closure` - called for each row with a `ResultSet`
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### query

    public void query(GString gstring, Closure closure) throws SQLException
    Performs the given SQL query, which should return a single `ResultSet` object. The given closure is called with the `ResultSet` as its argument. The query may contain GString expressions.

    Example usage:

         def location = 25
         sql.query "select * from PERSON where location_id < $location", { ResultSet rs ->
             while (rs.next()) println rs.getString('firstname')
         }

    All resources including the ResultSet are closed automatically after the closure is called.

    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
      `closure` - called for each row with a `ResultSet`
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `expand(Object)`

  - ### eachRow

    public void eachRow(String sql, Closure closure) throws SQLException
    Performs the given SQL query calling the given Closure with each row of the result set. The row will be a `GroovyResultSet` which is a `ResultSet` that supports accessing the fields using property style notation and ordinal index values.

    Example usages:

         sql.eachRow("select * from PERSON where firstname like 'S%'") { row ->
            println "$row.firstname ${row[2]}}"
         }

         sql.eachRow "call my_stored_proc_returning_resultset()", {
             println it.firstname
         }

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the sql statement
      `closure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs

  - ### eachRow

    public void eachRow(String sql, int offset, int maxRows, Closure closure) throws SQLException
    Performs the given SQL query calling the given `closure` with each row of the result set starting at the provided `offset`, and including up to `maxRows` number of rows. The row will be a `GroovyResultSet` which is a `ResultSet` that supports accessing the fields using property style notation and ordinal index values.

    Note that the underlying implementation is based on either invoking `ResultSet.absolute()`, or if the ResultSet type is `ResultSet.TYPE_FORWARD_ONLY`, the `ResultSet.next()` method is invoked equivalently. The first row of a ResultSet is 1, so passing in an offset of 1 or less has no effect on the initial positioning within the result set.

    Note that different database and JDBC driver implementations may work differently with respect to this method. Specifically, one should expect that `ResultSet.TYPE_FORWARD_ONLY` may be less efficient than a "scrollable" type.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the sql statement
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
      `closure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs

  - ### eachRow

    public void eachRow(String sql, Closure metaClosure, Closure rowClosure) throws SQLException
    Performs the given SQL query calling the given `rowClosure` with each row of the result set. The row will be a `GroovyResultSet` which is a `ResultSet` that supports accessing the fields using property style notation and ordinal index values. In addition, the `metaClosure` will be called once passing in the `ResultSetMetaData` as argument.

    Example usage:

         def printColNames = { meta ->
             (1..meta.columnCount).each {
                 print meta.getColumnLabel(it).padRight(20)
             }
             println()
         }
         def printRow = { row ->
             row.toRowResult().values().each{ print it.toString().padRight(20) }
             println()
         }
         sql.eachRow("select * from PERSON", printColNames, printRow)

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the sql statement
      `metaClosure` - called for meta data (only once after sql execution)
      `rowClosure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs

  - ### eachRow

    public void eachRow(String sql, Closure metaClosure, int offset, int maxRows, Closure rowClosure) throws SQLException
    Performs the given SQL query calling the given `rowClosure` with each row of the result set starting at the provided `offset`, and including up to `maxRows` number of rows. The row will be a `GroovyResultSet` which is a `ResultSet` that supports accessing the fields using property style notation and ordinal index values.

    In addition, the `metaClosure` will be called once passing in the `ResultSetMetaData` as argument.

    Note that the underlying implementation is based on either invoking `ResultSet.absolute()`, or if the ResultSet type is `ResultSet.TYPE_FORWARD_ONLY`, the `ResultSet.next()` method is invoked equivalently. The first row of a ResultSet is 1, so passing in an offset of 1 or less has no effect on the initial positioning within the result set.

    Note that different database and JDBC driver implementations may work differently with respect to this method. Specifically, one should expect that `ResultSet.TYPE_FORWARD_ONLY` may be less efficient than a "scrollable" type.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the sql statement
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
      `metaClosure` - called for meta data (only once after sql execution)
      `rowClosure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs

  - ### eachRow

    public void eachRow(String sql, List<Object> params, Closure metaClosure, int offset, int maxRows, Closure rowClosure) throws SQLException
    Performs the given SQL query calling the given `rowClosure` with each row of the result set starting at the provided `offset`, and including up to `maxRows` number of rows. The row will be a `GroovyResultSet` which is a `ResultSet` that supports accessing the fields using property style notation and ordinal index values.

    In addition, the `metaClosure` will be called once passing in the `ResultSetMetaData` as argument. The query may contain placeholder question marks which match the given list of parameters.

    Note that the underlying implementation is based on either invoking `ResultSet.absolute()`, or if the ResultSet type is `ResultSet.TYPE_FORWARD_ONLY`, the `ResultSet.next()` method is invoked equivalently. The first row of a ResultSet is 1, so passing in an offset of 1 or less has no effect on the initial positioning within the result set.

    Note that different database and JDBC driver implementations may work differently with respect to this method. Specifically, one should expect that `ResultSet.TYPE_FORWARD_ONLY` may be less efficient than a "scrollable" type.

    Parameters:
      `sql` - the sql statement
      `params` - a list of parameters
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
      `metaClosure` - called for meta data (only once after sql execution)
      `rowClosure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs

  - ### eachRow

    public void eachRow(String sql, Map map, Closure metaClosure, int offset, int maxRows, Closure rowClosure) throws SQLException
    A variant of `eachRow(String, java.util.List, groovy.lang.Closure, int, int, groovy.lang.Closure)` allowing the named parameters to be supplied in a map.
    Parameters:
      `sql` - the sql statement
      `map` - a map containing the named parameters
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
      `metaClosure` - called for meta data (only once after sql execution)
      `rowClosure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### eachRow

    public void eachRow(Map map, String sql, Closure metaClosure, int offset, int maxRows, Closure rowClosure) throws SQLException
    A variant of `eachRow(String, java.util.List, groovy.lang.Closure, int, int, groovy.lang.Closure)` allowing the named parameters to be supplied as named arguments.
    Parameters:
      `map` - a map containing the named parameters
      `sql` - the sql statement
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
      `metaClosure` - called for meta data (only once after sql execution)
      `rowClosure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### eachRow

    public void eachRow(String sql, List<Object> params, Closure metaClosure, Closure rowClosure) throws SQLException
    Performs the given SQL query calling the given Closure with each row of the result set. The row will be a `GroovyResultSet` which is a `ResultSet` that supports accessing the fields using property style notation and ordinal index values. In addition, the `metaClosure` will be called once passing in the `ResultSetMetaData` as argument. The query may contain placeholder question marks which match the given list of parameters.

    Example usage:

         def printColNames = { meta ->
             (1..meta.columnCount).each {
                 print meta.getColumnLabel(it).padRight(20)
             }
             println()
         }
         def printRow = { row ->
             row.toRowResult().values().each{ print it.toString().padRight(20) }
             println()
         }
         sql.eachRow("select * from PERSON where lastname like ?", ['%a%'], printColNames, printRow)

    This method supports named and named ordinal parameters. See the class Javadoc for more details.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the sql statement
      `params` - a list of parameters
      `metaClosure` - called for meta data (only once after sql execution)
      `rowClosure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs

  - ### eachRow

    public void eachRow(String sql, Map params, Closure metaClosure, Closure rowClosure) throws SQLException
    A variant of `eachRow(String, java.util.List, groovy.lang.Closure, groovy.lang.Closure)` useful when providing the named parameters as a map.
    Parameters:
      `sql` - the sql statement
      `params` - a map of named parameters
      `metaClosure` - called for meta data (only once after sql execution)
      `rowClosure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### eachRow

    public void eachRow(Map params, String sql, Closure metaClosure, Closure rowClosure) throws SQLException
    A variant of `eachRow(String, java.util.List, groovy.lang.Closure, groovy.lang.Closure)` useful when providing the named parameters as named arguments.
    Parameters:
      `params` - a map of named parameters
      `sql` - the sql statement
      `metaClosure` - called for meta data (only once after sql execution)
      `rowClosure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### eachRow

    public void eachRow(String sql, List<Object> params, Closure closure) throws SQLException
    Performs the given SQL query calling the given Closure with each row of the result set. The row will be a `GroovyResultSet` which is a `ResultSet` that supports accessing the fields using property style notation and ordinal index values. The query may contain placeholder question marks which match the given list of parameters.

    Example usage:

         sql.eachRow("select * from PERSON where lastname like ?", ['%a%']) { row ->
             println "${row[1]} $row.lastname"
         }

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the sql statement
      `params` - a list of parameters
      `closure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs

  - ### eachRow

    public void eachRow(String sql, Map params, Closure closure) throws SQLException
    A variant of `eachRow(String, java.util.List, groovy.lang.Closure)` useful when providing the named parameters as a map.
    Parameters:
      `sql` - the sql statement
      `params` - a map of named parameters
      `closure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### eachRow

    public void eachRow(Map params, String sql, Closure closure) throws SQLException
    A variant of `eachRow(String, java.util.List, groovy.lang.Closure)` useful when providing the named parameters as named arguments.
    Parameters:
      `params` - a map of named parameters
      `sql` - the sql statement
      `closure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### eachRow

    public void eachRow(String sql, List<Object> params, int offset, int maxRows, Closure closure) throws SQLException
    Performs the given SQL query calling the given `closure` with each row of the result set starting at the provided `offset`, and including up to `maxRows` number of rows. The row will be a `GroovyResultSet` which is a `ResultSet` that supports accessing the fields using property style notation and ordinal index values. The query may contain placeholder question marks which match the given list of parameters.

    Note that the underlying implementation is based on either invoking `ResultSet.absolute()`, or if the ResultSet type is `ResultSet.TYPE_FORWARD_ONLY`, the `ResultSet.next()` method is invoked equivalently. The first row of a ResultSet is 1, so passing in an offset of 1 or less has no effect on the initial positioning within the result set.

    Note that different database and JDBC driver implementations may work differently with respect to this method. Specifically, one should expect that `ResultSet.TYPE_FORWARD_ONLY` may be less efficient than a "scrollable" type.

    Parameters:
      `sql` - the sql statement
      `params` - a list of parameters
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
      `closure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs

  - ### eachRow

    public void eachRow(String sql, Map params, int offset, int maxRows, Closure closure) throws SQLException
    A variant of `eachRow(String, java.util.List, int, int, groovy.lang.Closure)` useful when providing the named parameters as a map.
    Parameters:
      `sql` - the sql statement
      `params` - a map of named parameters
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
      `closure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### eachRow

    public void eachRow(Map params, String sql, int offset, int maxRows, Closure closure) throws SQLException
    A variant of `eachRow(String, java.util.List, int, int, groovy.lang.Closure)` useful when providing the named parameters as named arguments.
    Parameters:
      `params` - a map of named parameters
      `sql` - the sql statement
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
      `closure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### eachRow

    public void eachRow(GString gstring, Closure metaClosure, Closure rowClosure) throws SQLException
    Performs the given SQL query calling the given Closure with each row of the result set. The row will be a `GroovyResultSet` which is a `ResultSet` that supports accessing the fields using property style notation and ordinal index values.

    In addition, the `metaClosure` will be called once passing in the `ResultSetMetaData` as argument. The query may contain GString expressions.

    Example usage:

         def location = 25
         def printColNames = { meta ->
             (1..meta.columnCount).each {
                 print meta.getColumnLabel(it).padRight(20)
             }
             println()
         }
         def printRow = { row ->
             row.toRowResult().values().each{ print it.toString().padRight(20) }
             println()
         }
         sql.eachRow("select * from PERSON where location_id < $location", printColNames, printRow)

    Resource handling is performed automatically where appropriate.

    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
      `metaClosure` - called for meta data (only once after sql execution)
      `rowClosure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `expand(Object)`

  - ### eachRow

    public void eachRow(GString gstring, Closure metaClosure, int offset, int maxRows, Closure rowClosure) throws SQLException
    Performs the given SQL query calling the given `closure` with each row of the result set starting at the provided `offset`, and including up to `maxRows` number of rows. The row will be a `GroovyResultSet` which is a `ResultSet` that supports accessing the fields using property style notation and ordinal index values. In addition, the `metaClosure` will be called once passing in the `ResultSetMetaData` as argument. The query may contain GString expressions.

    Note that the underlying implementation is based on either invoking `ResultSet.absolute()`, or if the ResultSet type is `ResultSet.TYPE_FORWARD_ONLY`, the `ResultSet.next()` method is invoked equivalently. The first row of a ResultSet is 1, so passing in an offset of 1 or less has no effect on the initial positioning within the result set.

    Note that different database and JDBC driver implementations may work differently with respect to this method. Specifically, one should expect that `ResultSet.TYPE_FORWARD_ONLY` may be less efficient than a "scrollable" type.

    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
      `metaClosure` - called for meta data (only once after sql execution)
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
      `rowClosure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs

  - ### eachRow

    public void eachRow(GString gstring, int offset, int maxRows, Closure closure) throws SQLException
    Performs the given SQL query calling the given `closure` with each row of the result set starting at the provided `offset`, and including up to `maxRows` number of rows. The row will be a `GroovyResultSet` which is a `ResultSet` that supports accessing the fields using property style notation and ordinal index values. The query may contain GString expressions.

    Note that the underlying implementation is based on either invoking `ResultSet.absolute()`, or if the ResultSet type is `ResultSet.TYPE_FORWARD_ONLY`, the `ResultSet.next()` method is invoked equivalently. The first row of a ResultSet is 1, so passing in an offset of 1 or less has no effect on the initial positioning within the result set.

    Note that different database and JDBC driver implementations may work differently with respect to this method. Specifically, one should expect that `ResultSet.TYPE_FORWARD_ONLY` may be less efficient than a "scrollable" type.

    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
      `closure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs

  - ### eachRow

    public void eachRow(GString gstring, Closure closure) throws SQLException
    Performs the given SQL query calling the given Closure with each row of the result set. The row will be a `GroovyResultSet` which is a `ResultSet` that supports accessing the fields using property style notation and ordinal index values. The query may contain GString expressions.

    Example usage:

         def location = 25
         sql.eachRow("select * from PERSON where location_id < $location") { row ->
             println row.firstname
         }

    Resource handling is performed automatically where appropriate.

    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
      `closure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `expand(Object)`

  - ### rows

    public List<GroovyRowResult> rows(String sql) throws SQLException
    Performs the given SQL query and return the rows of the result set.

    Example usage:

         def ans = sql.rows("select * from PERSON where firstname like 'S%'")
         println "Found ${ans.size()} rows"

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL statement
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs

  - ### rows

    public List<GroovyRowResult> rows(String sql, int offset, int maxRows) throws SQLException
    Performs the given SQL query and return a "page" of rows from the result set. A page is defined as starting at a 1-based offset, and containing a maximum number of rows.

    Note that the underlying implementation is based on either invoking `ResultSet.absolute()`, or if the ResultSet type is `ResultSet.TYPE_FORWARD_ONLY`, the `ResultSet.next()` method is invoked equivalently. The first row of a ResultSet is 1, so passing in an offset of 1 or less has no effect on the initial positioning within the result set.

    Note that different database and JDBC driver implementations may work differently with respect to this method. Specifically, one should expect that `ResultSet.TYPE_FORWARD_ONLY` may be less efficient than a "scrollable" type.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL statement
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs

  - ### rows

    public List<GroovyRowResult> rows(String sql, Closure metaClosure) throws SQLException
    Performs the given SQL query and return the rows of the result set. In addition, the `metaClosure` will be called once passing in the `ResultSetMetaData` as argument.

    Example usage:

         def printNumCols = { meta -> println "Found $meta.columnCount columns" }
         def ans = sql.rows("select * from PERSON", printNumCols)
         println "Found ${ans.size()} rows"

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL statement
      `metaClosure` - called with meta data of the ResultSet
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs

  - ### rows

    public List<GroovyRowResult> rows(String sql, int offset, int maxRows, Closure metaClosure) throws SQLException
    Performs the given SQL query and return a "page" of rows from the result set. A page is defined as starting at a 1-based offset, and containing a maximum number of rows. In addition, the `metaClosure` will be called once passing in the `ResultSetMetaData` as argument.

    Note that the underlying implementation is based on either invoking `ResultSet.absolute()`, or if the ResultSet type is `ResultSet.TYPE_FORWARD_ONLY`, the `ResultSet.next()` method is invoked equivalently. The first row of a ResultSet is 1, so passing in an offset of 1 or less has no effect on the initial positioning within the result set.

    Note that different database and JDBC driver implementations may work differently with respect to this method. Specifically, one should expect that `ResultSet.TYPE_FORWARD_ONLY` may be less efficient than a "scrollable" type.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL statement
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
      `metaClosure` - called for meta data (only once after sql execution)
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs

  - ### rows

    public List<GroovyRowResult> rows(String sql, List<Object> params) throws SQLException
    Performs the given SQL query and return the rows of the result set. The query may contain placeholder question marks which match the given list of parameters.

    Example usage:

         def ans = sql.rows("select * from PERSON where lastname like ?", ['%a%'])
         println "Found ${ans.size()} rows"

    This method supports named and named ordinal parameters by supplying such parameters in the `params` list. See the class Javadoc for more details.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL statement
      `params` - a list of parameters
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs

  - ### rows

    public List<GroovyRowResult> rows(Map params, String sql) throws SQLException
    A variant of `rows(String, java.util.List)` useful when providing the named parameters as named arguments.
    Parameters:
      `params` - a map containing the named parameters
      `sql` - the SQL statement
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### rows

    public List<GroovyRowResult> rows(String sql, List<Object> params, int offset, int maxRows) throws SQLException
    Performs the given SQL query and return a "page" of rows from the result set. A page is defined as starting at a 1-based offset, and containing a maximum number of rows. The query may contain placeholder question marks which match the given list of parameters.

    Note that the underlying implementation is based on either invoking `ResultSet.absolute()`, or if the ResultSet type is `ResultSet.TYPE_FORWARD_ONLY`, the `ResultSet.next()` method is invoked equivalently. The first row of a ResultSet is 1, so passing in an offset of 1 or less has no effect on the initial positioning within the result set.

    Note that different database and JDBC driver implementations may work differently with respect to this method. Specifically, one should expect that `ResultSet.TYPE_FORWARD_ONLY` may be less efficient than a "scrollable" type.

    This method supports named and named ordinal parameters by supplying such parameters in the `params` list. See the class Javadoc for more details.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL statement
      `params` - a list of parameters
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs

  - ### rows

    public List<GroovyRowResult> rows(String sql, Map params, int offset, int maxRows) throws SQLException
    A variant of `rows(String, java.util.List, int, int)` useful when providing the named parameters as a map.
    Parameters:
      `sql` - the SQL statement
      `params` - a map of named parameters
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### rows

    public List<GroovyRowResult> rows(Map params, String sql, int offset, int maxRows) throws SQLException
    A variant of `rows(String, java.util.List, int, int)` useful when providing the named parameters as named arguments.
    Parameters:
      `params` - a map of named parameters
      `sql` - the SQL statement
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### rows

    public List<GroovyRowResult> rows(String sql, Object[] params) throws SQLException
    Performs the given SQL query and return the rows of the result set.

    This method supports named and named ordinal parameters by supplying such parameters in the `params` array. See the class Javadoc for more details.

    An Object array variant of `rows(String, List)`.

    Parameters:
      `sql` - the SQL statement
      `params` - an array of parameters
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs

  - ### rows

    public List<GroovyRowResult> rows(String sql, Object[] params, int offset, int maxRows) throws SQLException
    Performs the given SQL query and return the rows of the result set.

    This method supports named and named ordinal parameters by supplying such parameters in the `params` array. See the class Javadoc for more details.

    An Object array variant of `rows(String, List, int, int)`.

    Parameters:
      `sql` - the SQL statement
      `params` - an array of parameters
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs

  - ### rows

    public List<GroovyRowResult> rows(String sql, List<Object> params, Closure metaClosure) throws SQLException
    Performs the given SQL query and return the rows of the result set. In addition, the `metaClosure` will be called once passing in the `ResultSetMetaData` as argument. The query may contain placeholder question marks which match the given list of parameters.

    Example usage:

         def printNumCols = { meta -> println "Found $meta.columnCount columns" }
         def ans = sql.rows("select * from PERSON where lastname like ?", ['%a%'], printNumCols)
         println "Found ${ans.size()} rows"

    This method supports named and named ordinal parameters by supplying such parameters in the `params` list. Here is an example:

         def printNumCols = { meta -> println "Found $meta.columnCount columns" }

         def mapParam = [foo: 'Smith']
         def domainParam = new MyDomainClass(bar: 'John')
         def qry = 'select * from PERSON where lastname=?1.foo and firstname=?2.bar'
         def ans = sql.rows(qry, [mapParam, domainParam], printNumCols)
         println "Found ${ans.size()} rows"

         def qry2 = 'select * from PERSON where firstname=:first and lastname=:last'
         def ans2 = sql.rows(qry2, [[last:'Smith', first:'John']], printNumCols)
         println "Found ${ans2.size()} rows"

    See the class Javadoc for more details.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL statement
      `params` - a list of parameters
      `metaClosure` - called for meta data (only once after sql execution)
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs

  - ### rows

    public List<GroovyRowResult> rows(String sql, Map params, Closure metaClosure) throws SQLException
    A variant of `rows(String, java.util.List, groovy.lang.Closure)` useful when providing the named parameters as a map.
    Parameters:
      `sql` - the SQL statement
      `params` - a map of named parameters
      `metaClosure` - called for meta data (only once after sql execution)
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### rows

    public List<GroovyRowResult> rows(Map params, String sql, Closure metaClosure) throws SQLException
    A variant of `rows(String, java.util.List, groovy.lang.Closure)` useful when providing the named parameters as named arguments.
    Parameters:
      `params` - a map of named parameters
      `sql` - the SQL statement
      `metaClosure` - called for meta data (only once after sql execution)
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### rows

    public List<GroovyRowResult> rows(String sql, List<Object> params, int offset, int maxRows, Closure metaClosure) throws SQLException
    Performs the given SQL query and return a "page" of rows from the result set. A page is defined as starting at a 1-based offset, and containing a maximum number of rows. In addition, the `metaClosure` will be called once passing in the `ResultSetMetaData` as argument. The query may contain placeholder question marks which match the given list of parameters.

    Note that the underlying implementation is based on either invoking `ResultSet.absolute()`, or if the ResultSet type is `ResultSet.TYPE_FORWARD_ONLY`, the `ResultSet.next()` method is invoked equivalently. The first row of a ResultSet is 1, so passing in an offset of 1 or less has no effect on the initial positioning within the result set.

    Note that different database and JDBC driver implementations may work differently with respect to this method. Specifically, one should expect that `ResultSet.TYPE_FORWARD_ONLY` may be less efficient than a "scrollable" type.

    This method supports named and named ordinal parameters by supplying such parameters in the `params` list. See the class Javadoc for more details.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL statement
      `params` - a list of parameters
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
      `metaClosure` - called for meta data (only once after sql execution)
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs

  - ### rows

    public List<GroovyRowResult> rows(String sql, Map params, int offset, int maxRows, Closure metaClosure) throws SQLException
    A variant of `rows(String, java.util.List, int, int, groovy.lang.Closure)` useful when providing the named parameters as a map.
    Parameters:
      `sql` - the SQL statement
      `params` - a map of named parameters
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
      `metaClosure` - called for meta data (only once after sql execution)
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### rows

    public List<GroovyRowResult> rows(Map params, String sql, int offset, int maxRows, Closure metaClosure) throws SQLException
    A variant of `rows(String, java.util.List, int, int, groovy.lang.Closure)` useful when providing the named parameters as named arguments.
    Parameters:
      `params` - a map of named parameters
      `sql` - the SQL statement
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
      `metaClosure` - called for meta data (only once after sql execution)
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### rows

    public List<GroovyRowResult> rows(GString sql, int offset, int maxRows) throws SQLException
    Performs the given SQL query and return a "page" of rows from the result set. A page is defined as starting at a 1-based offset, and containing a maximum number of rows. The query may contain GString expressions.

    Note that the underlying implementation is based on either invoking `ResultSet.absolute()`, or if the ResultSet type is `ResultSet.TYPE_FORWARD_ONLY`, the `ResultSet.next()` method is invoked equivalently. The first row of a ResultSet is 1, so passing in an offset of 1 or less has no effect on the initial positioning within the result set.

    Note that different database and JDBC driver implementations may work differently with respect to this method. Specifically, one should expect that `ResultSet.TYPE_FORWARD_ONLY` may be less efficient than a "scrollable" type.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL statement
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs

  - ### rows

    public List<GroovyRowResult> rows(GString gstring) throws SQLException
    Performs the given SQL query and return the rows of the result set. The query may contain GString expressions.

    Example usage:

         def location = 25
         def ans = sql.rows("select * from PERSON where location_id < $location")
         println "Found ${ans.size()} rows"

    Resource handling is performed automatically where appropriate.

    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `expand(Object)`

  - ### rows

    public List<GroovyRowResult> rows(GString gstring, Closure metaClosure) throws SQLException
    Performs the given SQL query and return the rows of the result set. In addition, the `metaClosure` will be called once passing in the `ResultSetMetaData` as argument. The query may contain GString expressions.

    Example usage:

         def location = 25
         def printNumCols = { meta -> println "Found $meta.columnCount columns" }
         def ans = sql.rows("select * from PERSON where location_id < $location", printNumCols)
         println "Found ${ans.size()} rows"

    Resource handling is performed automatically where appropriate.

    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
      `metaClosure` - called with meta data of the ResultSet
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `expand(Object)`

  - ### rows

    public List<GroovyRowResult> rows(GString gstring, int offset, int maxRows, Closure metaClosure) throws SQLException
    Performs the given SQL query and return a "page" of rows from the result set. A page is defined as starting at a 1-based offset, and containing a maximum number of rows. In addition, the `metaClosure` will be called once passing in the `ResultSetMetaData` as argument. The query may contain GString expressions.

    Note that the underlying implementation is based on either invoking `ResultSet.absolute()`, or if the ResultSet type is `ResultSet.TYPE_FORWARD_ONLY`, the `ResultSet.next()` method is invoked equivalently. The first row of a ResultSet is 1, so passing in an offset of 1 or less has no effect on the initial positioning within the result set.

    Note that different database and JDBC driver implementations may work differently with respect to this method. Specifically, one should expect that `ResultSet.TYPE_FORWARD_ONLY` may be less efficient than a "scrollable" type.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `gstring` - the SQL statement
      `offset` - the 1-based offset for the first row to be processed
      `maxRows` - the maximum number of rows to be processed
      `metaClosure` - called for meta data (only once after sql execution)
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs

  - ### firstRow

    public GroovyRowResult firstRow(String sql) throws SQLException
    Performs the given SQL query and return the first row of the result set.

    Example usage:

         def ans = sql.firstRow("select * from PERSON where firstname like 'S%'")
         println ans.firstname

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL statement
    Returns:
      a GroovyRowResult object or `null` if no row is found
    Throws:
      `SQLException` - if a database access error occurs

  - ### firstRow

    public GroovyRowResult firstRow(GString gstring) throws SQLException
    Performs the given SQL query and return the first row of the result set. The query may contain GString expressions.

    Example usage:

         def location = 25
         def ans = sql.firstRow("select * from PERSON where location_id < $location")
         println ans.firstname

    Resource handling is performed automatically where appropriate.

    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
    Returns:
      a GroovyRowResult object or `null` if no row is found
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `expand(Object)`

  - ### firstRow

    public GroovyRowResult firstRow(String sql, List<Object> params) throws SQLException
    Performs the given SQL query and return the first row of the result set. The query may contain placeholder question marks which match the given list of parameters.

    Example usages:

         def ans = sql.firstRow("select * from PERSON where lastname like ?", ['%a%'])
         println ans.firstname

    If your database returns scalar functions as ResultSets, you can also use firstRow to gain access to stored procedure results, e.g. using hsqldb 1.9 RC4:

         sql.execute """
             create function FullName(p_firstname VARCHAR(40)) returns VARCHAR(80)
             BEGIN atomic
             DECLARE ans VARCHAR(80);
             SET ans = (SELECT firstname || ' ' || lastname FROM PERSON WHERE firstname = p_firstname);
             RETURN ans;
             END
         """

         assert sql.firstRow("{call FullName(?)}", ['Sam'])[0] == 'Sam Pullara'

    This method supports named and named ordinal parameters by supplying such parameters in the `params` list. See the class Javadoc for more details.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL statement
      `params` - a list of parameters
    Returns:
      a GroovyRowResult object or `null` if no row is found
    Throws:
      `SQLException` - if a database access error occurs

  - ### firstRow

    public GroovyRowResult firstRow(Map params, String sql) throws SQLException
    A variant of `firstRow(String, java.util.List)` useful when providing the named parameters as named arguments.
    Parameters:
      `params` - a map containing the named parameters
      `sql` - the SQL statement
    Returns:
      a GroovyRowResult object or `null` if no row is found
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### firstRow

    public GroovyRowResult firstRow(String sql, Object[] params) throws SQLException
    Performs the given SQL query and return the first row of the result set.

    An Object array variant of `firstRow(String, List)`.

    This method supports named and named ordinal parameters by supplying such parameters in the `params` array. See the class Javadoc for more details.

    Parameters:
      `sql` - the SQL statement
      `params` - an array of parameters
    Returns:
      a GroovyRowResult object or `null` if no row is found
    Throws:
      `SQLException` - if a database access error occurs

  - ### execute

    public boolean execute(String sql) throws SQLException
    Executes the given piece of SQL. Also saves the updateCount, if any, for subsequent examination.

    Example usages:

         sql.execute "DROP TABLE IF EXISTS person"

         sql.execute """
             CREATE TABLE person (
                 id INTEGER NOT NULL,
                 firstname VARCHAR(100),
                 lastname VARCHAR(100),
                 location_id INTEGER
             )
         """

         sql.execute """
             INSERT INTO person (id, firstname, lastname, location_id) VALUES (4, 'Paul', 'King', 40)
         """
         assert sql.updateCount == 1

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL to execute
    Returns:
      `true` if the first result is a `ResultSet` object; `false` if it is an update count or there are no results
    Throws:
      `SQLException` - if a database access error occurs

  - ### execute

    public void execute(String sql, Closure processResults) throws SQLException
    Executes the given piece of SQL. Also calls the provided processResults Closure to process any ResultSet or UpdateCount results that executing the SQL might produce.

    Example usages:

         boolean first = true
         sql.execute "{call FindAllByFirst('J')}", { isResultSet, result ->
           if (first) {
             first = false
             assert !isResultSet && result == 0
           } else {
             assert isResultSet && result == [[ID:1, FIRSTNAME:'James', LASTNAME:'Strachan'], [ID:4, FIRSTNAME:'Jean', LASTNAME:'Gabin']]
           }
         }

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL to execute
      `processResults` - a Closure which will be passed two parameters: either `true` plus a list of GroovyRowResult values derived from `statement.getResultSet()` or `false` plus the update count from `statement.getUpdateCount()`. The closure will be called for each result produced from executing the SQL.
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      2.3.2

  - ### execute

    public boolean execute(String sql, List<Object> params) throws SQLException
    Executes the given piece of SQL with parameters. Also saves the updateCount, if any, for subsequent examination.

    Example usage:

         sql.execute """
             insert into PERSON (id, firstname, lastname, location_id) values (?, ?, ?, ?)
         """, [1, "Guillaume", "Laforge", 10]
         assert sql.updateCount == 1

    This method supports named and named ordinal parameters. See the class Javadoc for more details.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL statement
      `params` - a list of parameters
    Returns:
      `true` if the first result is a `ResultSet` object; `false` if it is an update count or there are no results
    Throws:
      `SQLException` - if a database access error occurs

  - ### execute

    public void execute(String sql, List<Object> params, Closure processResults) throws SQLException
    Executes the given piece of SQL with parameters. Also calls the provided processResults Closure to process any ResultSet or UpdateCount results that executing the SQL might produce.

    This method supports named and named ordinal parameters. See the class Javadoc for more details.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL statement
      `params` - a list of parameters
      `processResults` - a Closure which will be passed two parameters: either `true` plus a list of GroovyRowResult values derived from `statement.getResultSet()` or `false` plus the update count from `statement.getUpdateCount()`. The closure will be called for each result produced from executing the SQL.
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      2.3.2
    See Also:
      - `execute(String, Closure)`

  - ### execute

    public boolean execute(Map params, String sql) throws SQLException
    A variant of `execute(String, java.util.List)` useful when providing the named parameters as named arguments.
    Parameters:
      `params` - a map containing the named parameters
      `sql` - the SQL statement
    Returns:
      `true` if the first result is a `ResultSet` object; `false` if it is an update count or there are no results
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### execute

    public void execute(Map params, String sql, Closure processResults) throws SQLException
    A variant of `execute(String, java.util.List, Closure)` useful when providing the named parameters as named arguments.
    Parameters:
      `params` - a map containing the named parameters
      `sql` - the SQL statement
      `processResults` - a Closure which will be passed two parameters: either `true` plus a list of GroovyRowResult values derived from `statement.getResultSet()` or `false` plus the update count from `statement.getUpdateCount()`. The closure will be called for each result produced from executing the SQL.
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      2.3.2

  - ### execute

    public boolean execute(String sql, Object[] params) throws SQLException
    Executes the given piece of SQL with parameters.

    An Object array variant of `execute(String, List)`.

    This method supports named and named ordinal parameters by supplying such parameters in the `params` array. See the class Javadoc for more details.

    Parameters:
      `sql` - the SQL statement
      `params` - an array of parameters
    Returns:
      `true` if the first result is a `ResultSet` object; `false` if it is an update count or there are no results
    Throws:
      `SQLException` - if a database access error occurs

  - ### execute

    public void execute(String sql, Object[] params, Closure processResults) throws SQLException
    Executes the given piece of SQL with parameters.

    An Object array variant of `execute(String, List, Closure)`.

    This method supports named and named ordinal parameters by supplying such parameters in the `params` array. See the class Javadoc for more details.

    Parameters:
      `sql` - the SQL statement
      `params` - an array of parameters
      `processResults` - a Closure which will be passed two parameters: either `true` plus a list of GroovyRowResult values derived from `statement.getResultSet()` or `false` plus the update count from `statement.getUpdateCount()`. The closure will be called for each result produced from executing the SQL.
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      2.3.2
    See Also:
      - `execute(String, List, Closure)`

  - ### execute

    public boolean execute(GString gstring) throws SQLException
    Executes the given SQL with embedded expressions inside. Also saves the updateCount, if any, for subsequent examination.

    Example usage:

         def scott = [firstname: "Scott", lastname: "Davis", id: 5, location_id: 50]
         sql.execute """
             insert into PERSON (id, firstname, lastname, location_id) values ($scott.id, $scott.firstname, $scott.lastname, $scott.location_id)
         """
         assert sql.updateCount == 1

    Resource handling is performed automatically where appropriate.

    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
    Returns:
      `true` if the first result is a `ResultSet` object; `false` if it is an update count or there are no results
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `expand(Object)`

  - ### execute

    public void execute(GString gstring, Closure processResults) throws SQLException
    Executes the given SQL with embedded expressions inside. Also calls the provided processResults Closure to process any ResultSet or UpdateCount results that executing the SQL might produce. Resource handling is performed automatically where appropriate.
    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
      `processResults` - a Closure which will be passed two parameters: either `true` plus a list of GroovyRowResult values derived from `statement.getResultSet()` or `false` plus the update count from `statement.getUpdateCount()`. The closure will be called for each result produced from executing the SQL.
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      2.3.2
    See Also:
      - `expand(Object)`
      - `execute(String, List, Closure)`

  - ### executeInsert

    public List<List<Object>> executeInsert(String sql) throws SQLException
    Executes the given SQL statement (typically an INSERT statement). Use this variant when you want to receive the values of any auto-generated columns, such as an autoincrement ID field. See `executeInsert(GString)` for more details.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - The SQL statement to execute
    Returns:
      A list of the auto-generated column values for each inserted row (typically auto-generated keys)
    Throws:
      `SQLException` - if a database access error occurs

  - ### executeInsert

    public List<List<Object>> executeInsert(String sql, List<Object> params) throws SQLException
    Executes the given SQL statement (typically an INSERT statement). Use this variant when you want to receive the values of any auto-generated columns, such as an autoincrement ID field. The query may contain placeholder question marks which match the given list of parameters. See `executeInsert(GString)` for more details.

    This method supports named and named ordinal parameters. See the class Javadoc for more details.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - The SQL statement to execute
      `params` - The parameter values that will be substituted into the SQL statement's parameter slots
    Returns:
      A list of the auto-generated column values for each inserted row (typically auto-generated keys)
    Throws:
      `SQLException` - if a database access error occurs

  - ### executeInsert

    public List<GroovyRowResult> executeInsert(String sql, List<Object> params, List<String> keyColumnNames) throws SQLException
    Executes the given SQL statement (typically an INSERT statement). Use this variant when you want to receive the values of any auto-generated columns, such as an autoincrement ID field (or fields) and you know the column name(s) of the ID field(s). The query may contain placeholder question marks which match the given list of parameters. See `executeInsert(GString)` for more details.

    This method supports named and named ordinal parameters. See the class Javadoc for more details.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - The SQL statement to execute
      `params` - The parameter values that will be substituted into the SQL statement's parameter slots
      `keyColumnNames` - a list of column names indicating the columns that should be returned from the inserted row or rows (some drivers may be case sensitive, e.g. may require uppercase names)
    Returns:
      A list of the auto-generated row results for each inserted row (typically auto-generated keys)
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      2.3.2
    See Also:
      - `Connection.prepareStatement(String, String[])`

  - ### executeInsert

    public List<List<Object>> executeInsert(Map params, String sql) throws SQLException
    A variant of `executeInsert(String, java.util.List)` useful when providing the named parameters as named arguments.
    Parameters:
      `params` - a map containing the named parameters
      `sql` - The SQL statement to execute
    Returns:
      A list of the auto-generated column values for each inserted row (typically auto-generated keys)
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### executeInsert

    public List<GroovyRowResult> executeInsert(Map params, String sql, List<String> keyColumnNames) throws SQLException
    A variant of `executeInsert(String, List, List)` useful when providing the named parameters as named arguments. This variant allows you to receive the values of any auto-generated columns, such as an autoincrement ID field (or fields) when you know the column name(s) of the ID field(s).
    Parameters:
      `params` - a map containing the named parameters
      `sql` - The SQL statement to execute
      `keyColumnNames` - a list of column names indicating the columns that should be returned from the inserted row or rows (some drivers may be case sensitive, e.g. may require uppercase names)
    Returns:
      A list of the auto-generated row results for each inserted row (typically auto-generated keys)
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      2.3.2
    See Also:
      - `Connection.prepareStatement(String, String[])`

  - ### executeInsert

    public List<List<Object>> executeInsert(String sql, Object[] params) throws SQLException
    Executes the given SQL statement (typically an INSERT statement).

    An Object array variant of `executeInsert(String, List)`.

    This method supports named and named ordinal parameters by supplying such parameters in the `params` array. See the class Javadoc for more details.

    Parameters:
      `sql` - The SQL statement to execute
      `params` - The parameter values that will be substituted into the SQL statement's parameter slots
    Returns:
      A list of the auto-generated column values for each inserted row (typically auto-generated keys)
    Throws:
      `SQLException` - if a database access error occurs

  - ### executeInsert

    public List<GroovyRowResult> executeInsert(String sql, String[] keyColumnNames) throws SQLException
    Executes the given SQL statement (typically an INSERT statement). This variant allows you to receive the values of any auto-generated columns, such as an autoincrement ID field (or fields) when you know the column name(s) of the ID field(s).

    This method supports named and named ordinal parameters by supplying such parameters in the `params` array. See the class Javadoc for more details.

    Parameters:
      `sql` - The SQL statement to execute
      `keyColumnNames` - an array of column names indicating the columns that should be returned from the inserted row or rows (some drivers may be case sensitive, e.g. may require uppercase names)
    Returns:
      A list of the auto-generated row results for each inserted row (typically auto-generated keys)
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      2.3.2

  - ### executeInsert

    public List<GroovyRowResult> executeInsert(String sql, String[] keyColumnNames, Object[] params) throws SQLException
    Executes the given SQL statement (typically an INSERT statement). This variant allows you to receive the values of any auto-generated columns, such as an autoincrement ID field (or fields) when you know the column name(s) of the ID field(s).

    An array variant of `executeInsert(String, List, List)`.

    This method supports named and named ordinal parameters by supplying such parameters in the `params` array. See the class Javadoc for more details.

    Parameters:
      `sql` - The SQL statement to execute
      `keyColumnNames` - an array of column names indicating the columns that should be returned from the inserted row or rows (some drivers may be case sensitive, e.g. may require uppercase names)
      `params` - The parameter values that will be substituted into the SQL statement's parameter slots
    Returns:
      A list of the auto-generated row results for each inserted row (typically auto-generated keys)
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      2.3.2

  - ### executeInsert

    public List<List<Object>> executeInsert(GString gstring) throws SQLException
    Executes the given SQL statement (typically an INSERT statement). Use this variant when you want to receive the values of any auto-generated columns, such as an autoincrement ID field. The query may contain GString expressions.

    Generated key values can be accessed using array notation. For example, to return the second auto-generated column value of the third row, use `keys[3][1]`. The method is designed to be used with SQL INSERT statements, but is not limited to them.

    The standard use for this method is when a table has an autoincrement ID column and you want to know what the ID is for a newly inserted row. In this example, we insert a single row into a table in which the first column contains the autoincrement ID:

         def sql = Sql.newInstance("jdbc:mysql://localhost:3306/groovy",
                                   "user",
                                   "password",
                                   "com.mysql.jdbc.Driver")

         def keys = sql.executeInsert("insert into test_table (INT_DATA, STRING_DATA) "
                               + "VALUES (1, 'Key Largo')")

         def id = keys[0][0]

         // 'id' now contains the value of the new row's ID column.
         // It can be used to update an object representation's
         // id attribute for example.
         ...

    Resource handling is performed automatically where appropriate.

    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
    Returns:
      A list of the auto-generated column values for each inserted row (typically auto-generated keys)
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `expand(Object)`

  - ### executeInsert

    public List<GroovyRowResult> executeInsert(GString gstring, List<String> keyColumnNames) throws SQLException
    Executes the given SQL statement (typically an INSERT statement). Use this variant when you want to receive the values of any auto-generated columns, such as an autoincrement ID field (or fields) and you know the column name(s) of the ID field(s).

    Resource handling is performed automatically where appropriate.

    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
      `keyColumnNames` - a list of column names indicating the columns that should be returned from the inserted row or rows (some drivers may be case sensitive, e.g. may require uppercase names)
    Returns:
      A list of the auto-generated row results for each inserted row (typically auto-generated keys)
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      2.3.2
    See Also:
      - `Connection.prepareStatement(String, String[])`
      - `expand(Object)`

  - ### executeUpdate

    public int executeUpdate(String sql) throws SQLException
    Executes the given SQL update.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL to execute
    Returns:
      the number of rows updated or 0 for SQL statements that return nothing
    Throws:
      `SQLException` - if a database access error occurs

  - ### executeUpdate

    public int executeUpdate(String sql, List<Object> params) throws SQLException
    Executes the given SQL update with parameters.

    This method supports named and named ordinal parameters. See the class Javadoc for more details.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL statement
      `params` - a list of parameters
    Returns:
      the number of rows updated or 0 for SQL statements that return nothing
    Throws:
      `SQLException` - if a database access error occurs

  - ### executeUpdate

    public int executeUpdate(Map params, String sql) throws SQLException
    A variant of `executeUpdate(String, java.util.List)` useful when providing the named parameters as named arguments.
    Parameters:
      `params` - a map containing the named parameters
      `sql` - the SQL statement
    Returns:
      the number of rows updated or 0 for SQL statements that return nothing
    Throws:
      `SQLException` - if a database access error occurs
    Since:
      1.8.7

  - ### executeUpdate

    public int executeUpdate(String sql, Object[] params) throws SQLException
    Executes the given SQL update with parameters.

    An Object array variant of `executeUpdate(String, List)`.

    Parameters:
      `sql` - the SQL statement
      `params` - an array of parameters
    Returns:
      the number of rows updated or 0 for SQL statements that return nothing
    Throws:
      `SQLException` - if a database access error occurs

  - ### executeUpdate

    public int executeUpdate(GString gstring) throws SQLException
    Executes the given SQL update with embedded expressions inside.

    Resource handling is performed automatically where appropriate.

    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
    Returns:
      the number of rows updated or 0 for SQL statements that return nothing
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `expand(Object)`

  - ### call

    public int call(String sql) throws SQLException
    Performs a stored procedure call.

    Example usage (tested with MySQL) - suppose we have the following stored procedure:

         sql.execute """
             CREATE PROCEDURE HouseSwap(_first1 VARCHAR(50), _first2 VARCHAR(50))
             BEGIN
                 DECLARE _loc1 INT;
                 DECLARE _loc2 INT;
                 SELECT location_id into _loc1 FROM PERSON where firstname = _first1;
                 SELECT location_id into _loc2 FROM PERSON where firstname = _first2;
                 UPDATE PERSON
                 set location_id = case firstname
                     when _first1 then _loc2
                     when _first2 then _loc1
                 end
                 where (firstname = _first1 OR firstname = _first2);
             END
         """

    then you can invoke the procedure as follows:

         def rowsChanged = sql.call("{call HouseSwap('Guillaume', 'Paul')}")
         assert rowsChanged == 2

    Parameters:
      `sql` - the SQL statement
    Returns:
      the number of rows updated or 0 for SQL statements that return nothing
    Throws:
      `SQLException` - if a database access error occurs

  - ### call

    public int call(GString gstring) throws SQLException
    Performs a stored procedure call with the given embedded parameters.

    Example usage - see `call(String)` for more details about creating a `HouseSwap(IN name1, IN name2)` stored procedure. Once created, it can be called like this:

         def p1 = 'Paul'
         def p2 = 'Guillaume'
         def rowsChanged = sql.call("{call HouseSwap($p1, $p2)}")
         assert rowsChanged == 2

    Resource handling is performed automatically where appropriate.

    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
    Returns:
      the number of rows updated or 0 for SQL statements that return nothing
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `expand(Object)`
      - `call(String)`

  - ### call

    public int call(String sql, List<Object> params) throws SQLException
    Performs a stored procedure call with the given parameters.

    Example usage - see `call(String)` for more details about creating a `HouseSwap(IN name1, IN name2)` stored procedure. Once created, it can be called like this:

         def rowsChanged = sql.call("{call HouseSwap(?, ?)}", ['Guillaume', 'Paul'])
         assert rowsChanged == 2

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the SQL statement
      `params` - a list of parameters
    Returns:
      the number of rows updated or 0 for SQL statements that return nothing
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `call(String)`

  - ### call

    public int call(String sql, Object[] params) throws SQLException
    Performs a stored procedure call with the given parameters.

    An Object array variant of `call(String, List)`.

    Parameters:
      `sql` - the SQL statement
      `params` - an array of parameters
    Returns:
      the number of rows updated or 0 for SQL statements that return nothing
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `call(String)`

  - ### call

    public void call(String sql, List<Object> params, Closure closure) throws SQLException
    Performs a stored procedure call with the given parameters. The closure is called once with all the out parameters.

    Example usage - suppose we create a stored procedure (ignore its simplistic implementation):

         // Tested with MySql 5.0.75
         sql.execute """
             CREATE PROCEDURE Hemisphere(
                 IN p_firstname VARCHAR(50),
                 IN p_lastname VARCHAR(50),
                 OUT ans VARCHAR(50))
             BEGIN
             DECLARE loc INT;
             SELECT location_id into loc FROM PERSON where firstname = p_firstname and lastname = p_lastname;
             CASE loc
                 WHEN 40 THEN
                     SET ans = 'Southern Hemisphere';
                 ELSE
                     SET ans = 'Northern Hemisphere';
             END CASE;
             END;
         """

    we can now call the stored procedure as follows:

         sql.call '{call Hemisphere(?, ?, ?)}', ['Guillaume', 'Laforge', Sql.VARCHAR], { dwells ->
             println dwells
         }

    which will output '`Northern Hemisphere`'.

    We can also access stored functions with scalar return values where the return value will be treated as an OUT parameter. Here are examples for various databases for creating such a procedure:

         // Tested with MySql 5.0.75
         sql.execute """
             create function FullName(p_firstname VARCHAR(40)) returns VARCHAR(80)
             begin
                 declare ans VARCHAR(80);
                 SELECT CONCAT(firstname, ' ', lastname) INTO ans FROM PERSON WHERE firstname = p_firstname;
                 return ans;
             end
         """

         // Tested with MS SQLServer Express 2008
         sql.execute """
             create function FullName(@firstname VARCHAR(40)) returns VARCHAR(80)
             begin
                 declare @ans VARCHAR(80)
                 SET @ans = (SELECT firstname + ' ' + lastname FROM PERSON WHERE firstname = @firstname)
                 return @ans
             end
         """

         // Tested with Oracle XE 10g
         sql.execute """
             create function FullName(p_firstname VARCHAR) return VARCHAR is
             ans VARCHAR(80);
             begin
                 SELECT CONCAT(CONCAT(firstname, ' '), lastname) INTO ans FROM PERSON WHERE firstname = p_firstname;
                 return ans;
             end;
         """

    and here is how you access the stored function for all databases:

         sql.call("{? = call FullName(?)}", [Sql.VARCHAR, 'Sam']) { name ->
             assert name == 'Sam Pullara'
         }

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the sql statement
      `params` - a list of parameters
      `closure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs

  - ### call

    public void call(GString gstring, Closure closure) throws SQLException
    Performs a stored procedure call with the given parameters, calling the closure once with all result objects.

    See `call(String, List, Closure)` for more details about creating a `Hemisphere(IN first, IN last, OUT dwells)` stored procedure. Once created, it can be called like this:

         def first = 'Scott'
         def last = 'Davis'
         sql.call "{call Hemisphere($first, $last, ${Sql.VARCHAR})}", { dwells ->
             println dwells
         }

    As another example, see `call(String, List, Closure)` for more details about creating a `FullName(IN first)` stored function. Once created, it can be called like this:

         def first = 'Sam'
         sql.call("{$Sql.VARCHAR = call FullName($first)}") { name ->
             assert name == 'Sam Pullara'
         }

    Resource handling is performed automatically where appropriate.

    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
      `closure` - called for each row with a GroovyResultSet
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `call(String, List, Closure)`
      - `expand(Object)`

  - ### callWithRows

    public List<GroovyRowResult> callWithRows(GString gstring, Closure closure) throws SQLException
    Performs a stored procedure call with the given parameters, calling the closure once with all result objects, and also returning the rows of the ResultSet.

    Use this when calling a stored procedure that utilizes both output parameters and returns a single ResultSet.

    Once created, the stored procedure can be called like this:

         def first = 'Jeff'
         def last = 'Sheets'
         def rows = sql.callWithRows "{call Hemisphere2($first, $last, ${Sql.VARCHAR})}", { dwells ->
             println dwells
         }

    Resource handling is performed automatically where appropriate.

    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
      `closure` - called once with all out parameter results
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `callWithRows(String, List, Closure)`

  - ### callWithRows

    public List<GroovyRowResult> callWithRows(String sql, List<Object> params, Closure closure) throws SQLException
    Performs a stored procedure call with the given parameters, calling the closure once with all result objects, and also returning the rows of the ResultSet.

    Use this when calling a stored procedure that utilizes both output parameters and returns a single ResultSet.

    Once created, the stored procedure can be called like this:

         def rows = sql.callWithRows '{call Hemisphere2(?, ?, ?)}', ['Guillaume', 'Laforge', Sql.VARCHAR], { dwells ->
             println dwells
         }

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the sql statement
      `params` - a list of parameters
      `closure` - called once with all out parameter results
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `callWithRows(GString, Closure)`

  - ### callWithAllRows

    public List<List<GroovyRowResult>> callWithAllRows(GString gstring, Closure closure) throws SQLException
    Performs a stored procedure call with the given parameters, calling the closure once with all result objects, and also returning a list of lists with the rows of the ResultSet(s).

    Use this when calling a stored procedure that utilizes both output parameters and returns multiple ResultSets.

    Once created, the stored procedure can be called like this:

         def first = 'Jeff'
         def last = 'Sheets'
         def rowsList = sql.callWithAllRows "{call Hemisphere2($first, $last, ${Sql.VARCHAR})}", { dwells ->
             println dwells
         }

    Resource handling is performed automatically where appropriate.

    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
      `closure` - called once with all out parameter results
    Returns:
      a list containing lists of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `callWithAllRows(String, List, Closure)`

  - ### callWithAllRows

    public List<List<GroovyRowResult>> callWithAllRows(String sql, List<Object> params, Closure closure) throws SQLException
    Performs a stored procedure call with the given parameters, calling the closure once with all result objects, and also returning a list of lists with the rows of the ResultSet(s).

    Use this when calling a stored procedure that utilizes both output parameters and returns multiple ResultSets.

    Once created, the stored procedure can be called like this:

         def rowsList = sql.callWithAllRows '{call Hemisphere2(?, ?, ?)}', ['Guillaume', 'Laforge', Sql.VARCHAR], { dwells ->
             println dwells
         }

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the sql statement
      `params` - a list of parameters
      `closure` - called once with all out parameter results
    Returns:
      a list containing lists of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `callWithRows(GString, Closure)`

  - ### close

    public void close()
    If this SQL object was created with a Connection then this method closes the connection. If this SQL object was created from a DataSource then this method only frees any cached objects (statements in particular).
    Specified by:
      `close` in interface `AutoCloseable`

  - ### getDataSource

    public DataSource getDataSource()

  - ### commit

    public void commit() throws SQLException
    If this SQL object was created with a Connection then this method commits the connection. If this SQL object was created from a DataSource then this method does nothing.
    Throws:
      `SQLException` - if a database access error occurs

  - ### rollback

    public void rollback() throws SQLException
    If this SQL object was created with a Connection then this method rolls back the connection. If this SQL object was created from a DataSource then this method does nothing.
    Throws:
      `SQLException` - if a database access error occurs

  - ### getUpdateCount

    public int getUpdateCount()
    Returns:
      Returns the updateCount.

  - ### getConnection

    public Connection getConnection()
    If this instance was created with a single Connection then the connection is returned. Otherwise if this instance was created with a DataSource then this method returns null
    Returns:
      the connection wired into this object, or null if this object uses a DataSource

  - ### withStatement

    public void withStatement(Closure configureStatement)
    Allows a closure to be passed in to configure the JDBC statements before they are executed. It can be used to do things like set the query size etc. When this method is invoked, the supplied closure is saved. Statements subsequently created from other methods will then be configured using this closure. The statement being configured is passed into the closure as its single argument, e.g.:

         sql.withStatement{ stmt -> stmt.maxRows = 10 }
         def firstTenRows = sql.rows("select * from table")

    Parameters:
      `configureStatement` - the closure

  - ### withCleanupStatement

    public void withCleanupStatement(Closure cleanupStatement)
    Allows a closure to be passed in which acts as a hook for JDBC statements before they are closed. It can be used to do things like check SQL warnings, e.g.:

         sql.withCleanupStatement{ stmt -> assert !stmt.warnings }
         def rows = sql.rows("select * from table")

    Parameters:
      `cleanupStatement` - the closure
    Since:
      4.0.1

  - ### setCacheStatements

    public void setCacheStatements(boolean cacheStatements)
    Enables statement caching.
    if cacheStatements is true, cache is created and all created prepared statements will be cached. if cacheStatements is false, all cached statements will be properly closed.
    Parameters:
      `cacheStatements` - the new value

  - ### isCacheStatements

    public boolean isCacheStatements()
    Returns:
      boolean true if cache is enabled (default is false)

  - ### cacheConnection

    public void cacheConnection(Closure closure) throws SQLException
    Caches the connection used while the closure is active. If the closure takes a single argument, it will be called with the connection, otherwise it will be called with no arguments.
    Parameters:
      `closure` - the given closure
    Throws:
      `SQLException` - if a database error occurs

  - ### withTransaction

    public void withTransaction(Closure closure) throws SQLException
    Performs the closure within a transaction using a cached connection. If the closure takes a single argument, it will be called with the connection, otherwise it will be called with no arguments.
    Parameters:
      `closure` - the given closure
    Throws:
      `SQLException` - if a database error occurs

  - ### isWithinBatch

    public boolean isWithinBatch()
    Returns true if the current Sql object is currently executing a withBatch method call.
    Returns:
      true if a withBatch call is currently being executed.

  - ### withBatch

    public int[] withBatch(Closure closure) throws SQLException
    Performs the closure (containing batch operations) within a batch. Uses a batch size of zero, i.e. no automatic partitioning of batches.

    This means that `executeBatch()` will be called automatically after the `withBatch` closure has finished but may be called explicitly if desired as well for more fine-grained partitioning of the batch.

    The closure will be called with a single argument; the database statement (actually a `BatchingStatementWrapper` helper object) associated with this batch.

    Use it like this:

         def updateCounts = sql.withBatch { stmt ->
             stmt.addBatch("insert into TABLENAME ...")
             stmt.addBatch("insert into TABLENAME ...")
             stmt.addBatch("insert into TABLENAME ...")
             ...
         }

    For integrity and performance reasons, you may wish to consider executing your batch command(s) within a transaction:

         sql.withTransaction {
             def result1 = sql.withBatch { ... }
             ...
         }

    Parameters:
      `closure` - the closure containing batch and optionally other statements
    Returns:
      an array of update counts containing one element for each command in the batch. The elements of the array are ordered according to the order in which commands were added to the batch.
    Throws:
      `SQLException` - if a database access error occurs, or this method is called on a closed `Statement`, or the driver does not support batch statements. Throws `BatchUpdateException` (a subclass of `SQLException`) if one of the commands sent to the database fails to execute properly or attempts to return a result set.
    See Also:
      - `withBatch(int, Closure)`

  - ### withBatch

    public int[] withBatch(int batchSize, Closure closure) throws SQLException
    Performs the closure (containing batch operations) within a batch using a given batch size.

    After every `batchSize` `addBatch(sqlBatchOperation)` operations, automatically calls an `executeBatch()` operation to "chunk" up the database operations into partitions. Though not normally needed, you can also explicitly call `executeBatch()` which after executing the current batch, resets the batch count back to zero.

    The closure will be called with a single argument; the database statement (actually a `BatchingStatementWrapper` helper object) associated with this batch.

    Use it like this for batchSize of 20:

         def updateCounts = sql.withBatch(20) { stmt ->
             stmt.addBatch("insert into TABLENAME ...")
             stmt.addBatch("insert into TABLENAME ...")
             stmt.addBatch("insert into TABLENAME ...")
             ...
         }

    For integrity and performance reasons, you may wish to consider executing your batch command(s) within a transaction:

         sql.withTransaction {
             def result1 = sql.withBatch { ... }
             ...
         }

    Parameters:
      `batchSize` - partition the batch into batchSize pieces, i.e. after batchSize `addBatch()` invocations, call `executeBatch()` automatically; 0 means manual calls to executeBatch are required
      `closure` - the closure containing batch and optionally other statements
    Returns:
      an array of update counts containing one element for each command in the batch. The elements of the array are ordered according to the order in which commands were added to the batch.
    Throws:
      `SQLException` - if a database access error occurs, or this method is called on a closed `Statement`, or the driver does not support batch statements. Throws `BatchUpdateException` (a subclass of `SQLException`) if one of the commands sent to the database fails to execute properly or attempts to return a result set.
    See Also:
      - `withBatch(Closure)`
      - `BatchingStatementWrapper`
      - `Statement`

  - ### withBatch

    public int[] withBatch(String sql, Closure closure) throws SQLException
    Performs the closure (containing batch operations specific to an associated prepared statement) within a batch. Uses a batch size of zero, i.e. no automatic partitioning of batches.

    This means that `executeBatch()` will be called automatically after the `withBatch` closure has finished but may be called explicitly if desired as well for more fine-grained partitioning of the batch.

    The closure will be called with a single argument; the prepared statement (actually a `BatchingPreparedStatementWrapper` helper object) associated with this batch.

    An example:

         def updateCounts = sql.withBatch('insert into TABLENAME(a, b, c) values (?, ?, ?)') { ps ->
             ps.addBatch([10, 12, 5])
             ps.addBatch([7, 3, 98])
             ps.addBatch(22, 67, 11)
             def partialUpdateCounts = ps.executeBatch() // optional interim batching
             ps.addBatch(30, 40, 50)
             ...
         }

    For integrity and performance reasons, you may wish to consider executing your batch command(s) within a transaction:

         sql.withTransaction {
             def result1 = sql.withBatch { ... }
             ...
         }

    Parameters:
      `sql` - batch update statement
      `closure` - the closure containing batch statements (to bind parameters) and optionally other statements
    Returns:
      an array of update counts containing one element for each binding in the batch. The elements of the array are ordered according to the order in which commands were executed.
    Throws:
      `SQLException` - if a database access error occurs, or this method is called on a closed `Statement`, or the driver does not support batch statements. Throws `BatchUpdateException` (a subclass of `SQLException`) if one of the commands sent to the database fails to execute properly or attempts to return a result set.
    See Also:
      - `withBatch(int, String, Closure)`
      - `BatchingPreparedStatementWrapper`
      - `PreparedStatement`

  - ### withBatch

    public int[] withBatch(int batchSize, String sql, Closure closure) throws SQLException
    Performs the closure (containing batch operations specific to an associated prepared statement) within a batch using a given batch size.

    After every `batchSize` `addBatch(params)` operations, automatically calls an `executeBatch()` operation to "chunk" up the database operations into partitions. Though not normally needed, you can also explicitly call `executeBatch()` which after executing the current batch, resets the batch count back to zero.

    The closure will be called with a single argument; the prepared statement (actually a `BatchingPreparedStatementWrapper` helper object) associated with this batch.

    Below is an example using a batchSize of 20:

         def updateCounts = sql.withBatch(20, 'insert into TABLENAME(a, b, c) values (?, ?, ?)') { ps ->
             ps.addBatch(10, 12, 5)      // varargs style
             ps.addBatch([7, 3, 98])     // list
             ps.addBatch([22, 67, 11])
             ...
         }

    Named parameters (into maps or domain objects) are also supported:

         def updateCounts = sql.withBatch(20, 'insert into TABLENAME(a, b, c) values (:foo, :bar, :baz)') { ps ->
             ps.addBatch([foo:10, bar:12, baz:5])  // map
             ps.addBatch(foo:7, bar:3, baz:98)     // Groovy named args allow outer brackets to be dropped
             ...
         }

    Named ordinal parameters (into maps or domain objects) are also supported:

         def updateCounts = sql.withBatch(20, 'insert into TABLENAME(a, b, c) values (?1.foo, ?2.bar, ?2.baz)') { ps ->
             ps.addBatch([[foo:22], [bar:67, baz:11]])  // list of maps or domain objects
             ps.addBatch([foo:10], [bar:12, baz:5])     // varargs allows outer brackets to be dropped
             ps.addBatch([foo:7], [bar:3, baz:98])
             ...
         }
         // swap to batch size of 5 and illustrate simple and domain object cases ...
         class Person { String first, last }
         def updateCounts2 = sql.withBatch(5, 'insert into PERSON(id, first, last) values (?1, ?2.first, ?2.last)') { ps ->
             ps.addBatch(1, new Person(first:'Peter', last:'Pan'))
             ps.addBatch(2, new Person(first:'Snow', last:'White'))
             ...
         }

    For integrity and performance reasons, you may wish to consider executing your batch command(s) within a transaction:

         sql.withTransaction {
             def result1 = sql.withBatch { ... }
             ...
         }

    Parameters:
      `batchSize` - partition the batch into batchSize pieces, i.e. after batchSize `addBatch()` invocations, call `executeBatch()` automatically; 0 means manual calls to executeBatch are required if additional partitioning of the batch is required
      `sql` - batch update statement
      `closure` - the closure containing batch statements (to bind parameters) and optionally other statements
    Returns:
      an array of update counts containing one element for each binding in the batch. The elements of the array are ordered according to the order in which commands were executed.
    Throws:
      `SQLException` - if a database access error occurs, or this method is called on a closed `Statement`, or the driver does not support batch statements. Throws `BatchUpdateException` (a subclass of `SQLException`) if one of the commands sent to the database fails to execute properly or attempts to return a result set.
    See Also:
      - `BatchingPreparedStatementWrapper`
      - `PreparedStatement`

  - ### cacheStatements

    public void cacheStatements(Closure closure) throws SQLException
    Caches every created preparedStatement in Closure closure Every cached preparedStatement is closed after closure has been called. If the closure takes a single argument, it will be called with the connection, otherwise it will be called with no arguments.
    Parameters:
      `closure` - the given closure
    Throws:
      `SQLException` - if a database error occurs
    See Also:
      - `setCacheStatements(boolean)`

  - ### callWithRows

    protected List<List<GroovyRowResult>> callWithRows(String sql, List<Object> params, int processResultsSets, Closure closure) throws SQLException
    Base internal method for call(), callWithRows(), and callWithAllRows() style of methods.

    Performs a stored procedure call with the given parameters, calling the closure once with all result objects, and also returning the rows of the ResultSet(s) (if processResultSets is set to Sql.FIRST_RESULT_SET, Sql.ALL_RESULT_SETS)

    Main purpose of processResultSets param is to retain original call() method performance when this is set to Sql.NO_RESULT_SETS

    Resource handling is performed automatically where appropriate.

    Parameters:
      `sql` - the sql statement
      `params` - a list of parameters
      `processResultsSets` - the result sets to process, either Sql.NO_RESULT_SETS, Sql.FIRST_RESULT_SET, or Sql.ALL_RESULT_SETS
      `closure` - called once with all out parameter results
    Returns:
      a list of GroovyRowResult objects
    Throws:
      `SQLException` - if a database access error occurs
    See Also:
      - `callWithRows(String, List, Closure)`

  - ### executeQuery

    protected final ResultSet executeQuery(String sql) throws SQLException
    Useful helper method which handles resource management when executing a query which returns a result set. Derived classes of Sql can override "createQueryCommand" and then call this method to access the ResultSet returned from the provided query or alternatively can use the higher-level method of Sql which return result sets which are funnelled through this method, e.g. eachRow, query.
    Parameters:
      `sql` - query to execute
    Returns:
      the resulting ResultSet
    Throws:
      `SQLException` - if a database error occurs

  - ### executePreparedQuery

    protected final ResultSet executePreparedQuery(String sql, List<Object> params) throws SQLException
    Useful helper method which handles resource management when executing a prepared query which returns a result set. Derived classes of Sql can override "createPreparedQueryCommand" and then call this method to access the ResultSet returned from the provided query.
    Parameters:
      `sql` - query to execute
      `params` - parameters matching question mark placeholders in the query
    Returns:
      the resulting ResultSet
    Throws:
      `SQLException` - if a database error occurs

  - ### asList

    protected List<GroovyRowResult> asList(String sql, ResultSet rs) throws SQLException
    Hook to allow derived classes to override list of result collection behavior. The default behavior is to return a list of GroovyRowResult objects corresponding to each row in the ResultSet.
    Parameters:
      `sql` - query to execute
      `rs` - the ResultSet to process
    Returns:
      the resulting list of rows
    Throws:
      `SQLException` - if a database error occurs

  - ### asList

    protected List<GroovyRowResult> asList(String sql, ResultSet rs, Closure metaClosure) throws SQLException
    Hook to allow derived classes to override list of result collection behavior. The default behavior is to return a list of GroovyRowResult objects corresponding to each row in the ResultSet.
    Parameters:
      `sql` - query to execute
      `rs` - the ResultSet to process
      `metaClosure` - called for meta data (only once after sql execution)
    Returns:
      the resulting list of rows
    Throws:
      `SQLException` - if a database error occurs

  - ### asList

    protected List<GroovyRowResult> asList(String sql, ResultSet rs, int offset, int maxRows, Closure metaClosure) throws SQLException
    Throws:
      `SQLException`

  - ### asSql

    protected String asSql(GString gstring, List<Object> values)
    Hook to allow derived classes to override sql generation from GStrings.
    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
      `values` - the values to embed
    Returns:
      the SQL version of the given query using ? instead of any parameter
    See Also:
      - `expand(Object)`

  - ### nullify

    protected String nullify(String sql)
    Hook to allow derived classes to override null handling. Default behavior is to replace ?'"? references with NULLish
    Parameters:
      `sql` - the SQL statement
    Returns:
      the modified SQL String

  - ### findWhereKeyword

    protected int findWhereKeyword(String sql)
    Hook to allow derived classes to override where clause sniffing. Default behavior is to find the first 'where' keyword in the sql doing simple avoidance of the word 'where' within quotes.
    Parameters:
      `sql` - the SQL statement
    Returns:
      the index of the found keyword or -1 if not found

  - ### getParameters

    protected List<Object> getParameters(GString gstring)
    Hook to allow derived classes to override behavior associated with extracting params from a GString.
    Parameters:
      `gstring` - a GString containing the SQL query with embedded params
    Returns:
      extracts the parameters from the expression as a List
    See Also:
      - `expand(Object)`

  - ### setParameters

    protected void setParameters(List<Object> params, PreparedStatement statement) throws SQLException
    Hook to allow derived classes to override behavior associated with setting params for a prepared statement. Default behavior is to append the parameters to the given statement using `setObject`.
    Parameters:
      `params` - the parameters to append
      `statement` - the statement
    Throws:
      `SQLException` - if a database access error occurs

  - ### setObject

    protected void setObject(PreparedStatement statement, int i, Object value) throws SQLException
    Strategy method allowing derived classes to handle types differently such as for CLOBs etc.
    Parameters:
      `statement` - the statement of interest
      `i` - the index of the object of interest
      `value` - the new object value
    Throws:
      `SQLException` - if a database access error occurs

  - ### createConnection

    protected Connection createConnection() throws SQLException
    An extension point allowing derived classes to change the behavior of connection creation. The default behavior is to either use the supplied connection or obtain it from the supplied datasource.
    Returns:
      the connection associated with this Sql
    Throws:
      `SQLException` - if a SQL error occurs

  - ### closeResources

    protected void closeResources(Connection connection, Statement statement, ResultSet results)
    An extension point allowing derived classes to change the behavior of resource closing.
    Parameters:
      `connection` - the connection to close
      `statement` - the statement to close
      `results` - the results to close

  - ### closeResources

    protected void closeResources(Connection connection, Statement statement)
    An extension point allowing the behavior of resource closing to be overridden in derived classes.
    Parameters:
      `connection` - the connection to close
      `statement` - the statement to close

  - ### closeResources

    protected void closeResources(Connection connection)
    An extension point allowing the behavior of resource closing to be overridden in derived classes.
    Parameters:
      `connection` - the connection to close

  - ### configure

    protected void configure(Statement statement)
    Provides a hook for derived classes to be able to configure JDBC statements. Default behavior is to call a previously saved closure, if any, using the statement as a parameter.
    Parameters:
      `statement` - the statement to configure

  - ### cleanup

    protected void cleanup(Statement statement)
    Provides a hook for derived classes to be able to examine JDBC statements before cleanup/closing. Default behavior is to call a previously saved closure, if any, using the statement as a parameter.
    Parameters:
      `statement` - the statement to cleanup
    Since:
      4.0.1

  - ### checkForNamedParams

    public SqlWithParams checkForNamedParams(String sql, List<Object> params)

  - ### preCheckForNamedParams

    @Deprecated public SqlWithParams preCheckForNamedParams(String sql)
    Deprecated.
    Use `buildSqlWithIndexedProps(String)` instead

  - ### buildSqlWithIndexedProps

    protected SqlWithParams buildSqlWithIndexedProps(String sql)
    Hook to allow derived classes to override behavior associated with the parsing and indexing of parameters from a given sql statement.
    Parameters:
      `sql` - the sql statement to process
    Returns:
      a `SqlWithParams` instance containing the parsed sql and parameters containing the indexed location and property name of parameters or `null` if no parsing of the sql was performed.

  - ### getUpdatedParams

    public List<Object> getUpdatedParams(List<Object> params, List<Tuple> indexPropList)

  - ### isCacheNamedQueries

    public boolean isCacheNamedQueries()
    Returns:
      boolean true if caching is enabled (the default is true)

  - ### setCacheNamedQueries

    public void setCacheNamedQueries(boolean cacheNamedQueries)
    Enables named query caching.
    if cacheNamedQueries is true, cache is created and processed named queries will be cached. if cacheNamedQueries is false, no caching will occur saving memory at the cost of additional processing time.
    Parameters:
      `cacheNamedQueries` - the new value

  - ### isEnableNamedQueries

    public boolean isEnableNamedQueries()
    Returns:
      boolean true if named query processing is enabled (the default is true)

  - ### setEnableNamedQueries

    public void setEnableNamedQueries(boolean enableNamedQueries)
    Enables named query support:
    - if enableNamedQueries is true, queries with ':propname' and '?1.propname' style placeholders will be processed.
    - if enableNamedQueries is false, this feature will be turned off.
    Parameters:
      `enableNamedQueries` - the new value

  - ### createQueryCommand

    protected Sql.AbstractQueryCommand createQueryCommand(String sql)
    Factory for the QueryCommand command pattern object allows subclasses to supply implementations of the command class. The factory will be used in a pattern similar to:

         AbstractQueryCommand q = createQueryCommand("update TABLE set count = 0) where count is null");
         try {
             ResultSet rs = q.execute();
             return asList(rs);
         } finally {
             q.closeResources();
         }

    Parameters:
      `sql` - statement to be executed
    Returns:
      a command - invoke its execute() and closeResource() methods

  - ### createPreparedQueryCommand

    protected Sql.AbstractQueryCommand createPreparedQueryCommand(String sql, List<Object> queryParams)
    Factory for the PreparedQueryCommand command pattern object allows subclass to supply implementations of the command class.
    Parameters:
      `sql` - statement to be executed, including optional parameter placeholders (?)
      `queryParams` - List of parameter values corresponding to parameter placeholders
    Returns:
      a command - invoke its execute() and closeResource() methods
    See Also:
      - `createQueryCommand(String)`

  - ### setInternalConnection

    protected void setInternalConnection(Connection conn)
    Stub needed for testing. Called when a connection is opened by one of the command-pattern classes so that a test case can monitor the state of the connection through its subclass.
    Parameters:
      `conn` - the connection that is about to be used by a command