/*
 * @(#)Statement.java	1.40 03/12/19
 *
 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package java.sql;

/**
 * <P>The object used for executing a static SQL statement
 * and returning the results it produces.
 * <P>
 * By default, only one <code>ResultSet</code> object per <code>Statement</code>
 * object can be open at the same time. Therefore, if the reading of one 
 * <code>ResultSet</code> object is interleaved
 * with the reading of another, each must have been generated by
 * different <code>Statement</code> objects. All execution methods in the
 * <code>Statement</code> interface implicitly close a statment's current 
 * <code>ResultSet</code> object if an open one exists.
 *
 * @see Connection#createStatement
 * @see ResultSet 
 */
public interface Statement {

    /**
     * Executes the given SQL statement, which returns a single 
     * <code>ResultSet</code> object.
     *
     * @param sql an SQL statement to be sent to the database, typically a 
     *        static SQL <code>SELECT</code> statement
     * @return a <code>ResultSet</code> object that contains the data produced 
     *         by the given query; never <code>null</code> 
     * @exception SQLException if a database access error occurs or the given
     *            SQL statement produces anything other than a single
     *            <code>ResultSet</code> object
     */
    ResultSet executeQuery(String sql) throws SQLException;

    /**
     * Executes the given SQL statement, which may be an <code>INSERT</code>, 
     * <code>UPDATE</code>, or <code>DELETE</code> statement or an
     * SQL statement that returns nothing, such as an SQL DDL statement.
     *
     * @param sql an SQL <code>INSERT</code>, <code>UPDATE</code> or
     * <code>DELETE</code> statement or an SQL statement that returns nothing
     * @return either the row count for <code>INSERT</code>, <code>UPDATE</code>
     * or <code>DELETE</code> statements, or <code>0</code> for SQL statements 
     * that return nothing
     * @exception SQLException if a database access error occurs or the given
     *            SQL statement produces a <code>ResultSet</code> object
     */
    int executeUpdate(String sql) throws SQLException;

    /**
     * Releases this <code>Statement</code> object's database 
     * and JDBC resources immediately instead of waiting for
     * this to happen when it is automatically closed.
     * It is generally good practice to release resources as soon as
     * you are finished with them to avoid tying up database
     * resources.
     * <P>
     * Calling the method <code>close</code> on a <code>Statement</code>
     * object that is already closed has no effect.
     * <P>
     * <B>Note:</B> A <code>Statement</code> object is automatically closed 
     * when it is garbage collected. When a <code>Statement</code> object is 
     * closed, its current <code>ResultSet</code> object, if one exists, is 
     * also closed.  
     *
     * @exception SQLException if a database access error occurs
     */
    void close() throws SQLException;

    //----------------------------------------------------------------------

    /**
     * Retrieves the maximum number of bytes that can be
     * returned for character and binary column values in a <code>ResultSet</code> 
     * object produced by this <code>Statement</code> object.
     * This limit applies only to <code>BINARY</code>,
     * <code>VARBINARY</code>, <code>LONGVARBINARY</code>, <code>CHAR</code>,
     * <code>VARCHAR</code>, and <code>LONGVARCHAR</code>
     * columns.  If the limit is exceeded, the excess data is silently
     * discarded.
     *
     * @return the current column size limit for columns storing character and 
     *         binary values; zero means there is no limit 
     * @exception SQLException if a database access error occurs
     * @see #setMaxFieldSize
     */
    int getMaxFieldSize() throws SQLException;
    
    /**
     * Sets the limit for the maximum number of bytes in a <code>ResultSet</code>
     * column storing character or binary values to
     * the given number of bytes.  This limit applies
     * only to <code>BINARY</code>, <code>VARBINARY</code>,
     * <code>LONGVARBINARY</code>, <code>CHAR</code>, <code>VARCHAR</code>, and
     * <code>LONGVARCHAR</code> fields.  If the limit is exceeded, the excess data
     * is silently discarded. For maximum portability, use values
     * greater than 256.
     *
     * @param max the new column size limit in bytes; zero means there is no limit 
     * @exception SQLException if a database access error occurs 
     *            or the condition max >= 0 is not satisfied
     * @see #getMaxFieldSize
     */
    void setMaxFieldSize(int max) throws SQLException;

    /**
     * Retrieves the maximum number of rows that a
     * <code>ResultSet</code> object produced by this
     * <code>Statement</code> object can contain.  If this limit is exceeded, 
     * the excess rows are silently dropped.
     *
     * @return the current maximum number of rows for a <code>ResultSet</code>
     *         object produced by this <code>Statement</code> object; 
     *         zero means there is no limit
     * @exception SQLException if a database access error occurs
     * @see #setMaxRows
     */
    int getMaxRows() throws SQLException;

    /**
     * Sets the limit for the maximum number of rows that any
     * <code>ResultSet</code> object can contain to the given number.
     * If the limit is exceeded, the excess
     * rows are silently dropped.
     *
     * @param max the new max rows limit; zero means there is no limit 
     * @exception SQLException if a database access error occurs
     *            or the condition max >= 0 is not satisfied
     * @see #getMaxRows
     */
    void setMaxRows(int max) throws SQLException;

    /**
     * Sets escape processing on or off.
     * If escape scanning is on (the default), the driver will do
     * escape substitution before sending the SQL statement to the database.
     *
     * Note: Since prepared statements have usually been parsed prior
     * to making this call, disabling escape processing for 
     * <code>PreparedStatements</code> objects will have no effect.
     *
     * @param enable <code>true</code> to enable escape processing;
     *       <code>false</code> to disable it
     * @exception SQLException if a database access error occurs
     */
    void setEscapeProcessing(boolean enable) throws SQLException;

    /**
     * Retrieves the number of seconds the driver will
     * wait for a <code>Statement</code> object to execute. If the limit is exceeded, a
     * <code>SQLException</code> is thrown.
     *
     * @return the current query timeout limit in seconds; zero means there is 
     *         no limit 
     * @exception SQLException if a database access error occurs
     * @see #setQueryTimeout
     */
    int getQueryTimeout() throws SQLException;

    /**
     * Sets the number of seconds the driver will wait for a 
     * <code>Statement</code> object to execute to the given number of seconds.
     * If the limit is exceeded, an <code>SQLException</code> is thrown.
     *
     * @param seconds the new query timeout limit in seconds; zero means 
     *        there is no limit
     * @exception SQLException if a database access error occurs
     *            or the condition seconds >= 0 is not satisfied
     * @see #getQueryTimeout
     */
    void setQueryTimeout(int seconds) throws SQLException;

    /**
     * Cancels this <code>Statement</code> object if both the DBMS and
     * driver support aborting an SQL statement.
     * This method can be used by one thread to cancel a statement that
     * is being executed by another thread.
     *
     * @exception SQLException if a database access error occurs
     */
    void cancel() throws SQLException;

    /**
     * Retrieves the first warning reported by calls on this <code>Statement</code> object.
     * Subsequent <code>Statement</code> object warnings will be chained to this
     * <code>SQLWarning</code> object.
     *
     * <p>The warning chain is automatically cleared each time
     * a statement is (re)executed. This method may not be called on a closed
     * <code>Statement</code> object; doing so will cause an <code>SQLException</code>
     * to be thrown.
     *
     * <P><B>Note:</B> If you are processing a <code>ResultSet</code> object, any
     * warnings associated with reads on that <code>ResultSet</code> object 
     * will be chained on it rather than on the <code>Statement</code>
     * object that produced it.
     *
     * @return the first <code>SQLWarning</code> object or <code>null</code> 
     *         if there are no warnings
     * @exception SQLException if a database access error occurs or this 
     *            method is called on a closed statement
     */
    SQLWarning getWarnings() throws SQLException;

    /**
     * Clears all the warnings reported on this <code>Statement</code>
     * object. After a call to this method,
     * the method <code>getWarnings</code> will return 
     * <code>null</code> until a new warning is reported for this
     * <code>Statement</code> object.  
     *
     * @exception SQLException if a database access error occurs
     */
    void clearWarnings() throws SQLException;

    /**
     * Sets the SQL cursor name to the given <code>String</code>, which 
     * will be used by subsequent <code>Statement</code> object 
     * <code>execute</code> methods. This name can then be
     * used in SQL positioned update or delete statements to identify the
     * current row in the <code>ResultSet</code> object generated by this 
     * statement.  If the database does not support positioned update/delete, 
     * this method is a noop.  To insure that a cursor has the proper isolation
     * level to support updates, the cursor's <code>SELECT</code> statement 
     * should have the form <code>SELECT FOR UPDATE</code>.  If 
     * <code>FOR UPDATE</code> is not present, positioned updates may fail.
     *
     * <P><B>Note:</B> By definition, the execution of positioned updates and
     * deletes must be done by a different <code>Statement</code> object than 
     * the one that generated the <code>ResultSet</code> object being used for 
     * positioning. Also, cursor names must be unique within a connection.
     *
     * @param name the new cursor name, which must be unique within
     *             a connection
     * @exception SQLException if a database access error occurs
     */
    void setCursorName(String name) throws SQLException;
	
    //----------------------- Multiple Results --------------------------

    /**
     * Executes the given SQL statement, which may return multiple results.
     * In some (uncommon) situations, a single SQL statement may return
     * multiple result sets and/or update counts.  Normally you can ignore
     * this unless you are (1) executing a stored procedure that you know may
     * return multiple results or (2) you are dynamically executing an
     * unknown SQL string.  
     * <P>
     * The <code>execute</code> method executes an SQL statement and indicates the
     * form of the first result.  You must then use the methods 
     * <code>getResultSet</code> or <code>getUpdateCount</code>
     * to retrieve the result, and <code>getMoreResults</code> to
     * move to any subsequent result(s).
     *
     * @param sql any SQL statement
     * @return <code>true</code> if the first result is a <code>ResultSet</code> 
     *         object; <code>false</code> if it is an update count or there are 
     *         no results
     * @exception SQLException if a database access error occurs
     * @see #getResultSet
     * @see #getUpdateCount
     * @see #getMoreResults 
     */
    boolean execute(String sql) throws SQLException;
	
    /**
     *  Retrieves the current result as a <code>ResultSet</code> object. 
     *  This method should be called only once per result.
     *
     * @return the current result as a <code>ResultSet</code> object or
     * <code>null</code> if the result is an update count or there are no more results
     * @exception SQLException if a database access error occurs
     * @see #execute 
     */
    ResultSet getResultSet() throws SQLException; 

    /**
     *  Retrieves the current result as an update count;
     *  if the result is a <code>ResultSet</code> object or there are no more results, -1
     *  is returned. This method should be called only once per result.
     * 
     * @return the current result as an update count; -1 if the current result is a
     * <code>ResultSet</code> object or there are no more results
     * @exception SQLException if a database access error occurs
     * @see #execute 
     */
    int getUpdateCount() throws SQLException; 

    /**
     * Moves to this <code>Statement</code> object's next result, returns
     * <code>true</code> if it is a <code>ResultSet</code> object, and
     * implicitly closes any current <code>ResultSet</code>
     * object(s) obtained with the method <code>getResultSet</code>.
     *
     * <P>There are no more results when the following is true:
     * <PRE>
     *     // stmt is a Statement object
     *     ((stmt.getMoreResults() == false) && (stmt.getUpdateCount() == -1))
     * </PRE>
     *
     * @return <code>true</code> if the next result is a <code>ResultSet</code>
     *         object; <code>false</code> if it is an update count or there are 
     *         no more results
     * @exception SQLException if a database access error occurs
     * @see #execute 
     */
    boolean getMoreResults() throws SQLException; 


    //--------------------------JDBC 2.0-----------------------------


    /**
     * Gives the driver a hint as to the direction in which
     * rows will be processed in <code>ResultSet</code>
     * objects created using this <code>Statement</code> object.  The 
     * default value is <code>ResultSet.FETCH_FORWARD</code>.
     * <P>
     * Note that this method sets the default fetch direction for 
     * result sets generated by this <code>Statement</code> object.
     * Each result set has its own methods for getting and setting
     * its own fetch direction.
     *
     * @param direction the initial direction for processing rows
     * @exception SQLException if a database access error occurs
     * or the given direction
     * is not one of <code>ResultSet.FETCH_FORWARD</code>,
     * <code>ResultSet.FETCH_REVERSE</code>, or <code>ResultSet.FETCH_UNKNOWN</code>
     * @since 1.2
     * @see #getFetchDirection
     */
    void setFetchDirection(int direction) throws SQLException;

    /**
     * Retrieves the direction for fetching rows from
     * database tables that is the default for result sets
     * generated from this <code>Statement</code> object.
     * If this <code>Statement</code> object has not set
     * a fetch direction by calling the method <code>setFetchDirection</code>,
     * the return value is implementation-specific.
     *
     * @return the default fetch direction for result sets generated
     *          from this <code>Statement</code> object
     * @exception SQLException if a database access error occurs
     * @since 1.2
     * @see #setFetchDirection
     */
    int getFetchDirection() throws SQLException;

    /**
     * Gives the JDBC driver a hint as to the number of rows that should 
     * be fetched from the database when more rows are needed.  The number 
     * of rows specified affects only result sets created using this 
     * statement. If the value specified is zero, then the hint is ignored.
     * The default value is zero.
     *
     * @param rows the number of rows to fetch
     * @exception SQLException if a database access error occurs, or the
     *        condition 0 <= <code>rows</code> <= <code>this.getMaxRows()</code> 
     *        is not satisfied.
     * @since 1.2
     * @see #getFetchSize
     */
    void setFetchSize(int rows) throws SQLException;
  
    /**
     * Retrieves the number of result set rows that is the default 
     * fetch size for <code>ResultSet</code> objects
     * generated from this <code>Statement</code> object.
     * If this <code>Statement</code> object has not set
     * a fetch size by calling the method <code>setFetchSize</code>,
     * the return value is implementation-specific.
     *
     * @return the default fetch size for result sets generated
     *          from this <code>Statement</code> object
     * @exception SQLException if a database access error occurs
     * @since 1.2
     * @see #setFetchSize
     */
    int getFetchSize() throws SQLException;

    /**
     * Retrieves the result set concurrency for <code>ResultSet</code> objects
     * generated by this <code>Statement</code> object.
     *
     * @return either <code>ResultSet.CONCUR_READ_ONLY</code> or
     * <code>ResultSet.CONCUR_UPDATABLE</code>
     * @exception SQLException if a database access error occurs
     * @since 1.2
     */
    int getResultSetConcurrency() throws SQLException;

    /**
     * Retrieves the result set type for <code>ResultSet</code> objects
     * generated by this <code>Statement</code> object.
     *
     * @return one of <code>ResultSet.TYPE_FORWARD_ONLY</code>,
     * <code>ResultSet.TYPE_SCROLL_INSENSITIVE</code>, or	
     * <code>ResultSet.TYPE_SCROLL_SENSITIVE</code>
     * @exception SQLException if a database access error occurs
     * @since 1.2
     */
    int getResultSetType()  throws SQLException;

    /**
     * Adds the given SQL command to the current list of commmands for this
     * <code>Statement</code> object. The commands in this list can be
     * executed as a batch by calling the method <code>executeBatch</code>.
     * <P>
     * <B>NOTE:</B>  This method is optional.
     *
     * @param sql typically this is a static SQL <code>INSERT</code> or 
     * <code>UPDATE</code> statement
     * @exception SQLException if a database access error occurs, or the
     * driver does not support batch updates
     * @see #executeBatch
     * @since 1.2
     */
    void addBatch( String sql ) throws SQLException;

    /**
     * Empties this <code>Statement</code> object's current list of 
     * SQL commands.
     * <P>
     * <B>NOTE:</B>  This method is optional.
     *
     * @exception SQLException if a database access error occurs or the
     * driver does not support batch updates
     * @see #addBatch
     * @since 1.2
     */
    void clearBatch() throws SQLException;

    /**
     * Submits a batch of commands to the database for execution and
     * if all commands execute successfully, returns an array of update counts.
     * The <code>int</code> elements of the array that is returned are ordered
     * to correspond to the commands in the batch, which are ordered 
     * according to the order in which they were added to the batch.
     * The elements in the array returned by the method <code>executeBatch</code>
     * may be one of the following:
     * <OL>
     * <LI>A number greater than or equal to zero -- indicates that the
     * command was processed successfully and is an update count giving the
     * number of rows in the database that were affected by the command's
     * execution
     * <LI>A value of <code>SUCCESS_NO_INFO</code> -- indicates that the command was
     * processed successfully but that the number of rows affected is
     * unknown
     * <P> 
     * If one of the commands in a batch update fails to execute properly,
     * this method throws a <code>BatchUpdateException</code>, and a JDBC
     * driver may or may not continue to process the remaining commands in
     * the batch.  However, the driver's behavior must be consistent with a
     * particular DBMS, either always continuing to process commands or never
     * continuing to process commands.  If the driver continues processing
     * after a failure, the array returned by the method
     * <code>BatchUpdateException.getUpdateCounts</code>
     * will contain as many elements as there are commands in the batch, and
     * at least one of the elements will be the following:
     * <P> 
     * <LI>A value of <code>EXECUTE_FAILED</code> -- indicates that the command failed
     * to execute successfully and occurs only if a driver continues to
     * process commands after a command fails
     * </OL>
     * <P>
     * A driver is not required to implement this method.
     * The possible implementations and return values have been modified in
     * the Java 2 SDK, Standard Edition, version 1.3 to
     * accommodate the option of continuing to proccess commands in a batch
     * update after a <code>BatchUpdateException</code> obejct has been thrown.
     *
     * @return 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.
     * @exception SQLException if a database access error occurs or the
     * driver does not support batch statements. Throws {@link BatchUpdateException}
     * (a subclass of <code>SQLException</code>) if one of the commands sent to the
     * database fails to execute properly or attempts to return a result set.
     * @since 1.3
     */
    int[] executeBatch() throws SQLException;

    /**
     * Retrieves the <code>Connection</code> object
     * that produced this <code>Statement</code> object.
     * @return the connection that produced this statement
     * @exception SQLException if a database access error occurs
     * @since 1.2
     */
    Connection getConnection()  throws SQLException;

  //--------------------------JDBC 3.0-----------------------------
    
    /** 
     * The constant indicating that the current <code>ResultSet</code> object 
     * should be closed when calling <code>getMoreResults</code>.
     *
     * @since 1.4
     */
    int CLOSE_CURRENT_RESULT = 1;

    /**
     * The constant indicating that the current <code>ResultSet</code> object
     * should not be closed when calling <code>getMoreResults</code>.
     *
     * @since 1.4
     */
    int KEEP_CURRENT_RESULT = 2;

    /**
     * The constant indicating that all <code>ResultSet</code> objects that
     * have previously been kept open should be closed when calling
     * <code>getMoreResults</code>.
     *
     * @since 1.4
     */
    int CLOSE_ALL_RESULTS = 3;

    /**
     * The constant indicating that a batch statement executed successfully
     * but that no count of the number of rows it affected is available.
     *
     * @since 1.4
     */
    int SUCCESS_NO_INFO = -2;

    /**
     * The constant indicating that an error occured while executing a
     * batch statement.
     *
     * @since 1.4
     */
    int EXECUTE_FAILED = -3;

    /**
     * The constant indicating that generated keys should be made 
     * available for retrieval.
     *
     * @since 1.4
     */
    int RETURN_GENERATED_KEYS = 1;

    /**
     * The constant indicating that generated keys should not be made 
     * available for retrieval.
     *
     * @since 1.4
     */
    int NO_GENERATED_KEYS = 2;

    /**
     * Moves to this <code>Statement</code> object's next result, deals with
     * any current <code>ResultSet</code> object(s) according  to the instructions
     * specified by the given flag, and returns
     * <code>true</code> if the next result is a <code>ResultSet</code> object.
     *
     * <P>There are no more results when the following is true:
     * <PRE>
     *     // stmt is a Statement object
     *     ((stmt.getMoreResults() == false) && (stmt.getUpdateCount() == -1))
     * </PRE>
     *
     * @param current one of the following <code>Statement</code>
     *        constants indicating what should happen to current 
     *        <code>ResultSet</code> objects obtained using the method
     *        <code>getResultSet</code>:
     *        <code>Statement.CLOSE_CURRENT_RESULT</code>, 
     *        <code>Statement.KEEP_CURRENT_RESULT</code>, or
     *        <code>Statement.CLOSE_ALL_RESULTS</code>
     * @return <code>true</code> if the next result is a <code>ResultSet</code> 
     *         object; <code>false</code> if it is an update count or there are no 
     *         more results
     * @exception SQLException if a database access error occurs or the argument
	 *         supplied is not one of the following:
     *        <code>Statement.CLOSE_CURRENT_RESULT</code>, 
     *        <code>Statement.KEEP_CURRENT_RESULT</code>, or
     *        <code>Statement.CLOSE_ALL_RESULTS</code>
     * @since 1.4
     * @see #execute
     */
    boolean getMoreResults(int current) throws SQLException;

    /**
     * Retrieves any auto-generated keys created as a result of executing this
     * <code>Statement</code> object. If this <code>Statement</code> object did 
     * not generate any keys, an empty <code>ResultSet</code>
     * object is returned.
     *
     * @return a <code>ResultSet</code> object containing the auto-generated key(s) 
     *         generated by the execution of this <code>Statement</code> object
     * @exception SQLException if a database access error occurs
     * @since 1.4
     */
    ResultSet getGeneratedKeys() throws SQLException;

    /**
     * Executes the given SQL statement and signals the driver with the
     * given flag about whether the
     * auto-generated keys produced by this <code>Statement</code> object
     * should be made available for retrieval. 
     *
     * @param sql must be an SQL <code>INSERT</code>, <code>UPDATE</code> or
     *        <code>DELETE</code> statement or an SQL statement that 
     *        returns nothing
     * @param autoGeneratedKeys a flag indicating whether auto-generated keys
     *        should be made available for retrieval;
     *         one of the following constants:
     *         <code>Statement.RETURN_GENERATED_KEYS</code>
     *         <code>Statement.NO_GENERATED_KEYS</code>
     * @return either the row count for <code>INSERT</code>, <code>UPDATE</code>
     *         or <code>DELETE</code> statements, or <code>0</code> for SQL 
     *         statements that return nothing
     * @exception SQLException if a database access error occurs, the given
     *            SQL statement returns a <code>ResultSet</code> object, or
     *            the given constant is not one of those allowed
     * @since 1.4
     */
    int executeUpdate(String sql, int autoGeneratedKeys) throws SQLException;

    /**
     * Executes the given SQL statement and signals the driver that the
     * auto-generated keys indicated in the given array should be made available
     * for retrieval.  The driver will ignore the array if the SQL statement
     * is not an <code>INSERT</code> statement.
     *
     * @param sql an SQL <code>INSERT</code>, <code>UPDATE</code> or
     *        <code>DELETE</code> statement or an SQL statement that returns nothing,
     *        such as an SQL DDL statement
     * @param columnIndexes an array of column indexes indicating the columns
     *        that should be returned from the inserted row
     * @return either the row count for <code>INSERT</code>, <code>UPDATE</code>,
     *         or <code>DELETE</code> statements, or 0 for SQL statements 
     *         that return nothing
     * @exception SQLException if a database access error occurs, the SQL
     *            statement returns a <code>ResultSet</code> object, or the
	 *            second argument supplied to this method is not an <code>int</code> array
	 *            whose elements are valid column indexes 
     * @since 1.4
     */
    int executeUpdate(String sql, int columnIndexes[]) throws SQLException;

    /**
     * Executes the given SQL statement and signals the driver that the
     * auto-generated keys indicated in the given array should be made available
     * for retrieval.  The driver will ignore the array if the SQL statement
     * is not an <code>INSERT</code> statement.
     *
     * @param sql an SQL <code>INSERT</code>, <code>UPDATE</code> or
     *        <code>DELETE</code> statement or an SQL statement that returns nothing
     * @param columnNames an array of the names of the columns that should be 
     *        returned from the inserted row
     * @return either the row count for <code>INSERT</code>, <code>UPDATE</code>,
     *         or <code>DELETE</code> statements, or 0 for SQL statements 
     *         that return nothing
     * @exception SQLException if a database access error occurs, the SQL
     *            statement returns a <code>ResultSet</code> object, or the
	 *            second argument supplied to this method is not a <code>String</code> array
     *            whose elements are valid column names
     *
     * @since 1.4
     */
    int executeUpdate(String sql, String columnNames[]) throws SQLException;

    /**
     * Executes the given SQL statement, which may return multiple results,
     * and signals the driver that any
     * auto-generated keys should be made available
     * for retrieval.  The driver will ignore this signal if the SQL statement
     * is not an <code>INSERT</code> statement.
     * <P>
     * In some (uncommon) situations, a single SQL statement may return
     * multiple result sets and/or update counts.  Normally you can ignore
     * this unless you are (1) executing a stored procedure that you know may
     * return multiple results or (2) you are dynamically executing an
     * unknown SQL string.  
     * <P>
     * The <code>execute</code> method executes an SQL statement and indicates the
     * form of the first result.  You must then use the methods 
     * <code>getResultSet</code> or <code>getUpdateCount</code>
     * to retrieve the result, and <code>getMoreResults</code> to
     * move to any subsequent result(s).
     *
     * @param sql any SQL statement
     * @param autoGeneratedKeys a constant indicating whether auto-generated 
     *        keys should be made available for retrieval using the method
     *        <code>getGeneratedKeys</code> one of the following constants:
     *        <code>Statement.RETURN_GENERATED_KEYS</code> or
     *	      <code>Statement.NO_GENERATED_KEYS</code>
     * @return <code>true</code> if the first result is a <code>ResultSet</code>
     *         object; <code>false</code> if it is an update count or there are
     *         no results
     * @exception SQLException if a database access error occurs or the second 
	 *         parameter supplied to this method is not 
     *         <code>Statement.RETURN_GENERATED_KEYS</code> or
	 *         <code>Statement.NO_GENERATED_KEYS</code>.
     * @see #getResultSet
     * @see #getUpdateCount
     * @see #getMoreResults
     * @see #getGeneratedKeys
     *
     * @since 1.4 
     */
    boolean execute(String sql, int autoGeneratedKeys) throws SQLException;

    /**
     * Executes the given SQL statement, which may return multiple results,
     * and signals the driver that the
     * auto-generated keys indicated in the given array should be made available
     * for retrieval.  This array contains the indexes of the columns in the 
     * target table that contain the auto-generated keys that should be made
     * available. The driver will ignore the array if the given SQL statement
     * is not an <code>INSERT</code> statement.
     * <P>
     * Under some (uncommon) situations, a single SQL statement may return
     * multiple result sets and/or update counts.  Normally you can ignore
     * this unless you are (1) executing a stored procedure that you know may
     * return multiple results or (2) you are dynamically executing an
     * unknown SQL string.  
     * <P>
     * The <code>execute</code> method executes an SQL statement and indicates the
     * form of the first result.  You must then use the methods 
     * <code>getResultSet</code> or <code>getUpdateCount</code>
     * to retrieve the result, and <code>getMoreResults</code> to
     * move to any subsequent result(s).
     *
     * @param sql any SQL statement
     * @param columnIndexes an array of the indexes of the columns in the 
     *        inserted row that should be  made available for retrieval by a
     *        call to the method <code>getGeneratedKeys</code>
     * @return <code>true</code> if the first result is a <code>ResultSet</code> 
     *         object; <code>false</code> if it is an update count or there 
     *         are no results
     * @exception SQLException if a database access error occurs or the 
     *            elements in the <code>int</code> array passed to this method
     *            are not valid column indexes
     * @see #getResultSet
     * @see #getUpdateCount
     * @see #getMoreResults
     *
     * @since 1.4
     */
    boolean execute(String sql, int columnIndexes[]) throws SQLException;

    /**
     * Executes the given SQL statement, which may return multiple results,
     * and signals the driver that the
     * auto-generated keys indicated in the given array should be made available
     * for retrieval. This array contains the names of the columns in the 
     * target table that contain the auto-generated keys that should be made
     * available. The driver will ignore the array if the given SQL statement
     * is not an <code>INSERT</code> statement.
     * <P>
     * In some (uncommon) situations, a single SQL statement may return
     * multiple result sets and/or update counts.  Normally you can ignore
     * this unless you are (1) executing a stored procedure that you know may
     * return multiple results or (2) you are dynamically executing an
     * unknown SQL string.  
     * <P>
     * The <code>execute</code> method executes an SQL statement and indicates the
     * form of the first result.  You must then use the methods 
     * <code>getResultSet</code> or <code>getUpdateCount</code>
     * to retrieve the result, and <code>getMoreResults</code> to
     * move to any subsequent result(s).
     *
     * @param sql any SQL statement
     * @param columnNames an array of the names of the columns in the inserted
     *        row that should be made available for retrieval by a call to the
     *        method <code>getGeneratedKeys</code>
     * @return <code>true</code> if the next result is a <code>ResultSet</code> 
     *         object; <code>false</code> if it is an update count or there 
     *         are no more results
     * @exception SQLException if a database access error occurs or the 
	 *          elements of the <code>String</code> array passed to this
     *          method are not valid column names
     * @see #getResultSet
     * @see #getUpdateCount
     * @see #getMoreResults
     * @see #getGeneratedKeys
     *
     * @since 1.4 
     */
    boolean execute(String sql, String columnNames[]) throws SQLException;

   /**
     * Retrieves the result set holdability for <code>ResultSet</code> objects
     * generated by this <code>Statement</code> object.
     *
     * @return either <code>ResultSet.HOLD_CURSORS_OVER_COMMIT</code> or
     *         <code>ResultSet.CLOSE_CURSORS_AT_COMMIT</code>
     * @exception SQLException if a database access error occurs
     *
     * @since 1.4
     */
    int getResultSetHoldability() throws SQLException;

}