/*
 * @(#)Connection.java	1.41 03/01/23
 *
 * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package java.sql;

/**
 * <P>A connection (session) with a specific
 * database. SQL statements are executed and results are returned
 * within the context of a connection.
 * <P>
 * A <code>Connection</code> object's database is able to provide information
 * describing its tables, its supported SQL grammar, its stored
 * procedures, the capabilities of this connection, and so on. This
 * information is obtained with the <code>getMetaData</code> method.
 *
 * <P><B>Note:</B> By default a <code>Connection</code> object is in
 * auto-commit mode, which means that it automatically commits changes 
 * after executing each statement. If auto-commit mode has been
 * disabled, the method <code>commit</code> must be called explicitly in
 * order to commit changes; otherwise, database changes will not be saved.
 * <P>
 * A new <code>Connection</code> object created using the JDBC 2.1 core API
 * has an initially empty type map associated with it. A user may enter a
 * custom mapping for a UDT in this type map.
 * When a UDT is retrieved from a data source with the
 * method <code>ResultSet.getObject</code>, the <code>getObject</code> method
 * will check the connection's type map to see if there is an entry for that
 * UDT.  If so, the <code>getObject</code> method will map the UDT to the
 * class indicated.  If there is no entry, the UDT will be mapped using the
 * standard mapping.
 * <p>
 * A user may create a new type map, which is a <code>java.util.Map</code>
 * object, make an entry in it, and pass it to the <code>java.sql</code>
 * methods that can perform custom mapping.  In this case, the method
 * will use the given type map instead of the one associated with
 * the connection.
 * <p>
 * For example, the following code fragment specifies that the SQL
 * type <code>ATHLETES</code> will be mapped to the class
 * <code>Athletes</code> in the Java programming language.
 * The code fragment retrieves the type map for the <code>Connection
 * </code> object <code>con</code>, inserts the entry into it, and then sets
 * the type map with the new entry as the connection's type map.
 * <pre>
 *      java.util.Map map = con.getTypeMap();
 *      map.put("mySchemaName.ATHLETES", Class.forName("Athletes"));
 *      con.setTypeMap(map);
 * </pre>
 *
 * @see DriverManager#getConnection
 * @see Statement 
 * @see ResultSet
 * @see DatabaseMetaData
 */
public interface Connection {

    /**
     * Creates a <code>Statement</code> object for sending
     * SQL statements to the database.
     * SQL statements without parameters are normally
     * executed using <code>Statement</code> objects. If the same SQL statement 
     * is executed many times, it may be more efficient to use a 
     * <code>PreparedStatement</code> object.
     * <P>
     * Result sets created using the returned <code>Statement</code>
     * object will by default be type <code>TYPE_FORWARD_ONLY</code>
     * and have a concurrency level of <code>CONCUR_READ_ONLY</code>.
     *
     * @return a new default <code>Statement</code> object 
     * @exception SQLException if a database access error occurs
     */
    Statement createStatement() throws SQLException;

    /**
     * Creates a <code>PreparedStatement</code> object for sending
     * parameterized SQL statements to the database.
     * <P>
     * A SQL statement with or without IN parameters can be
     * pre-compiled and stored in a <code>PreparedStatement</code> object. This
     * object can then be used to efficiently execute this statement
     * multiple times.
     *
     * <P><B>Note:</B> This method is optimized for handling
     * parametric SQL statements that benefit from precompilation. If
     * the driver supports precompilation,
     * the method <code>prepareStatement</code> will send
     * the statement to the database for precompilation. Some drivers
     * may not support precompilation. In this case, the statement may
     * not be sent to the database until the <code>PreparedStatement</code> 
     * object is executed.  This has no direct effect on users; however, it does
     * affect which methods throw certain <code>SQLException</code> objects.
     * <P>
     * Result sets created using the returned <code>PreparedStatement</code>
     * object will by default be type <code>TYPE_FORWARD_ONLY</code>
     * and have a concurrency level of <code>CONCUR_READ_ONLY</code>.
     *
     * @param sql an SQL statement that may contain one or more '?' IN
     * parameter placeholders
     * @return a new default <code>PreparedStatement</code> object containing the
     * pre-compiled SQL statement 
     * @exception SQLException if a database access error occurs
     */
    PreparedStatement prepareStatement(String sql)
	throws SQLException;

    /**
     * Creates a <code>CallableStatement</code> object for calling
     * database stored procedures.
     * The <code>CallableStatement</code> object provides
     * methods for setting up its IN and OUT parameters, and
     * methods for executing the call to a stored procedure.
     *
     * <P><B>Note:</B> This method is optimized for handling stored
     * procedure call statements. Some drivers may send the call
     * statement to the database when the method <code>prepareCall</code>
     * is done; others
     * may wait until the <code>CallableStatement</code> object
     * is executed. This has no
     * direct effect on users; however, it does affect which method
     * throws certain SQLExceptions.
     * <P>
     * Result sets created using the returned <code>CallableStatement</code>
     * object will by default be type <code>TYPE_FORWARD_ONLY</code>
     * and have a concurrency level of <code>CONCUR_READ_ONLY</code>.
     *
     * @param sql an SQL statement that may contain one or more '?'
     * parameter placeholders. Typically this  statement is a JDBC
     * function call escape string.
     * @return a new default <code>CallableStatement</code> object containing the
     * pre-compiled SQL statement 
     * @exception SQLException if a database access error occurs
     */
    CallableStatement prepareCall(String sql) throws SQLException;
						
    /**
     * Converts the given SQL statement into the system's native SQL grammar.
     * A driver may convert the JDBC SQL grammar into its system's
     * native SQL grammar prior to sending it. This method returns the
     * native form of the statement that the driver would have sent.
     *
     * @param sql an SQL statement that may contain one or more '?'
     * parameter placeholders
     * @return the native form of this statement
     * @exception SQLException if a database access error occurs
     */
    String nativeSQL(String sql) throws SQLException;

    /**
     * Sets this connection's auto-commit mode to the given state.
     * If a connection is in auto-commit mode, then all its SQL
     * statements will be executed and committed as individual
     * transactions.  Otherwise, its SQL statements are grouped into
     * transactions that are terminated by a call to either
     * the method <code>commit</code> or the method <code>rollback</code>.
     * By default, new connections are in auto-commit
     * mode.
     * <P>
     * The commit occurs when the statement completes or the next
     * execute occurs, whichever comes first. In the case of
     * statements returning a <code>ResultSet</code> object, 
     * the statement completes when the last row of the 
     * <code>ResultSet</code> object has been retrieved or the
     * <code>ResultSet</code> object has been closed. In advanced cases, a single
     * statement may return multiple results as well as output
     * parameter values. In these cases, the commit occurs when all results and
     * output parameter values have been retrieved.
     * <P>
     * <B>NOTE:</B>  If this method is called during a transaction, the
     * transaction is committed.
     *
     * @param autoCommit <code>true</code> to enable auto-commit mode; 
     *         <code>false</code> to disable it
     * @exception SQLException if a database access error occurs
     * @see #getAutoCommit
     */
    void setAutoCommit(boolean autoCommit) throws SQLException;

    /**
     * Retrieves the current auto-commit mode for this <code>Connection</code>
     * object.
     *
     * @return the current state of this <code>Connection</code> object's 
     *         auto-commit mode
     * @exception SQLException if a database access error occurs
     * @see #setAutoCommit 
     */
    boolean getAutoCommit() throws SQLException;

    /**
     * Makes all changes made since the previous
     * commit/rollback permanent and releases any database locks
     * currently held by this <code>Connection</code> object. 
     * This method should be
     * used only when auto-commit mode has been disabled.
     *
     * @exception SQLException if a database access error occurs or this
     *            <code>Connection</code> object is in auto-commit mode
     * @see #setAutoCommit 
     */
    void commit() throws SQLException;

    /**
     * Undoes all changes made in the current transaction
     * and releases any database locks currently held
     * by this <code>Connection</code> object. This method should be 
     * used only when auto-commit mode has been disabled.
     *
     * @exception SQLException if a database access error occurs or this
     *            <code>Connection</code> object is in auto-commit mode
     * @see #setAutoCommit 
     */
    void rollback() throws SQLException;

    /**
     * Releases this <code>Connection</code> object's database and JDBC resources
     * immediately instead of waiting for them to be automatically released.
     * <P>
     * Calling the method <code>close</code> on a <code>Connection</code>
     * object that is already closed is a no-op.
     * <P>
     * <B>Note:</B> A <code>Connection</code> object is automatically 
     * closed when it is garbage collected. Certain fatal errors also 
     * close a <code>Connection</code> object.
     *
     * @exception SQLException if a database access error occurs
     */
    void close() throws SQLException;

    /**
     * Retrieves whether this <code>Connection</code> object has been
     * closed.  A connection is closed if the method <code>close</code>
     * has been called on it or if certain fatal errors have occurred.
     * This method is guaranteed to return <code>true</code> only when
     * it is called after the method <code>Connection.close</code> has
     * been called.
     * <P>
     * This method generally cannot be called to determine whether a
     * connection to a database is valid or invalid.  A typical client
     * can determine that a connection is invalid by catching any
     * exceptions that might be thrown when an operation is attempted.
     *
     * @return <code>true</code> if this <code>Connection</code> object 
     *         is closed; <code>false</code> if it is still open
     * @exception SQLException if a database access error occurs
     */
    boolean isClosed() throws SQLException;

    //======================================================================
    // Advanced features:

    /**
     * Retrieves a <code>DatabaseMetaData</code> object that contains
     * metadata about the database to which this
     * <code>Connection</code> object represents a connection.
     * The metadata includes information about the database's
     * tables, its supported SQL grammar, its stored
     * procedures, the capabilities of this connection, and so on.
     *
     * @return a <code>DatabaseMetaData</code> object for this 
     *         <code>Connection</code> object
     * @exception SQLException if a database access error occurs
     */
    DatabaseMetaData getMetaData() throws SQLException;

    /**
     * Puts this connection in read-only mode as a hint to the driver to enable 
     * database optimizations.
     *
     * <P><B>Note:</B> This method cannot be called during a transaction.
     *
     * @param readOnly <code>true</code> enables read-only mode; 
     *        <code>false</code> disables it
     * @exception SQLException if a database access error occurs or this
     *            method is called during a transaction
     */
    void setReadOnly(boolean readOnly) throws SQLException;

    /**
     * Retrieves whether this <code>Connection</code> 
     * object is in read-only mode.
     *
     * @return <code>true</code> if this <code>Connection</code> object
     *         is read-only; <code>false</code> otherwise
     * @exception SQLException if a database access error occurs
     */
    boolean isReadOnly() throws SQLException;

    /**
     * Sets the given catalog name in order to select 	
     * a subspace of this <code>Connection</code> object's database 
     * in which to work.
     * <P>
     * If the driver does not support catalogs, it will
     * silently ignore this request.
     *
     * @param catalog the name of a catalog (subspace in this 
     *        <code>Connection</code> object's database) in which to work
     * @exception SQLException if a database access error occurs
     * @see #getCatalog
     */
    void setCatalog(String catalog) throws SQLException;

    /**
     * Retrieves this <code>Connection</code> object's current catalog name.
     *
     * @return the current catalog name or <code>null</code> if there is none
     * @exception SQLException if a database access error occurs
     * @see #setCatalog
     */
    String getCatalog() throws SQLException;

    /**
     * A constant indicating that transactions are not supported. 
     */
    int TRANSACTION_NONE	     = 0;

    /**
     * A constant indicating that
     * dirty reads, non-repeatable reads and phantom reads can occur.
     * This level allows a row changed by one transaction to be read
     * by another transaction before any changes in that row have been
     * committed (a "dirty read").  If any of the changes are rolled back, 
     * the second transaction will have retrieved an invalid row.
     */
    int TRANSACTION_READ_UNCOMMITTED = 1;

    /**
     * A constant indicating that
     * dirty reads are prevented; non-repeatable reads and phantom
     * reads can occur.  This level only prohibits a transaction
     * from reading a row with uncommitted changes in it.
     */
    int TRANSACTION_READ_COMMITTED   = 2;

    /**
     * A constant indicating that
     * dirty reads and non-repeatable reads are prevented; phantom
     * reads can occur.  This level prohibits a transaction from
     * reading a row with uncommitted changes in it, and it also
     * prohibits the situation where one transaction reads a row,
     * a second transaction alters the row, and the first transaction
     * rereads the row, getting different values the second time
     * (a "non-repeatable read").
     */
    int TRANSACTION_REPEATABLE_READ  = 4;

    /**
     * A constant indicating that
     * dirty reads, non-repeatable reads and phantom reads are prevented.
     * This level includes the prohibitions in
     * <code>TRANSACTION_REPEATABLE_READ</code> and further prohibits the 
     * situation where one transaction reads all rows that satisfy
     * a <code>WHERE</code> condition, a second transaction inserts a row that
     * satisfies that <code>WHERE</code> condition, and the first transaction
     * rereads for the same condition, retrieving the additional
     * "phantom" row in the second read.
     */
    int TRANSACTION_SERIALIZABLE     = 8;

    /**
     * Attempts to change the transaction isolation level for this
     * <code>Connection</code> object to the one given.
     * The constants defined in the interface <code>Connection</code>
     * are the possible transaction isolation levels.
     * <P>
     * <B>Note:</B> If this method is called during a transaction, the result
     * is implementation-defined.
     *
     * @param level one of the following <code>Connection</code> constants:
     *        <code>Connection.TRANSACTION_READ_UNCOMMITTED</code>,
     *        <code>Connection.TRANSACTION_READ_COMMITTED</code>,
     *        <code>Connection.TRANSACTION_REPEATABLE_READ</code>, or
     *        <code>Connection.TRANSACTION_SERIALIZABLE</code>.
     *        (Note that <code>Connection.TRANSACTION_NONE</code> cannot be used 
     *        because it specifies that transactions are not supported.)
     * @exception SQLException if a database access error occurs
     *            or the given parameter is not one of the <code>Connection</code>
     *            constants
     * @see DatabaseMetaData#supportsTransactionIsolationLevel 
     * @see #getTransactionIsolation
     */
    void setTransactionIsolation(int level) throws SQLException;

    /**
     * Retrieves this <code>Connection</code> object's current 
     * transaction isolation level.
     *
     * @return the current transaction isolation level, which will be one
     *         of the following constants:
     *        <code>Connection.TRANSACTION_READ_UNCOMMITTED</code>, 
     *        <code>Connection.TRANSACTION_READ_COMMITTED</code>,
     *        <code>Connection.TRANSACTION_REPEATABLE_READ</code>, 
     *        <code>Connection.TRANSACTION_SERIALIZABLE</code>, or
     *        <code>Connection.TRANSACTION_NONE</code>.
     * @exception SQLException if a database access error occurs
     * @see #setTransactionIsolation
     */
    int getTransactionIsolation() throws SQLException;

    /**
     * Retrieves the first warning reported by calls on this 
     * <code>Connection</code> object.  If there is more than one
     * warning, subsequent warnings will be chained to the first one
     * and can be retrieved by calling the method
     * <code>SQLWarning.getNextWarning</code> on the warning 
     * that was retrieved previously.
     * <P>
     * This method may not be
     * called on a closed connection; doing so will cause an
     * <code>SQLException</code> to be thrown.
     *
     * <P><B>Note:</B> Subsequent warnings will be chained to this
     * SQLWarning.
     *
     * @return the first <code>SQLWarning</code> object or <code>null</code>
     *         if there are none 
     * @exception SQLException if a database access error occurs or
     *            this method is called on a closed connection
     * @see SQLWarning
     */
    SQLWarning getWarnings() throws SQLException;

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


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

    /**
     * Creates a <code>Statement</code> object that will generate
     * <code>ResultSet</code> objects with the given type and concurrency.
     * This method is the same as the <code>createStatement</code> method
     * above, but it allows the default result set
     * type and concurrency to be overridden.
     *
     * @param resultSetType a result set type; one of 
     *        <code>ResultSet.TYPE_FORWARD_ONLY</code>,
     *        <code>ResultSet.TYPE_SCROLL_INSENSITIVE</code>, or
     *        <code>ResultSet.TYPE_SCROLL_SENSITIVE</code>
     * @param resultSetConcurrency a concurrency type; one of
     *        <code>ResultSet.CONCUR_READ_ONLY</code> or
     *        <code>ResultSet.CONCUR_UPDATABLE</code>
     * @return a new <code>Statement</code> object that will generate
     *         <code>ResultSet</code> objects with the given type and
     *         concurrency
     * @exception SQLException if a database access error occurs
     *         or the given parameters are not <code>ResultSet</code> 
     *         constants indicating type and concurrency
     * @since 1.2
     */
    Statement createStatement(int resultSetType, int resultSetConcurrency) 
	throws SQLException;

    /**
     *
     * Creates a <code>PreparedStatement</code> object that will generate
     * <code>ResultSet</code> objects with the given type and concurrency.
     * This method is the same as the <code>prepareStatement</code> method
     * above, but it allows the default result set
     * type and concurrency to be overridden.
     *
     * @param sql a <code>String</code> object that is the SQL statement to
     *            be sent to the database; may contain one or more ? IN
     *            parameters
     * @param resultSetType a result set type; one of 
     *         <code>ResultSet.TYPE_FORWARD_ONLY</code>, 
     *         <code>ResultSet.TYPE_SCROLL_INSENSITIVE</code>, or
     *         <code>ResultSet.TYPE_SCROLL_SENSITIVE</code>
     * @param resultSetConcurrency a concurrency type; one of
     *         <code>ResultSet.CONCUR_READ_ONLY</code> or
     *         <code>ResultSet.CONCUR_UPDATABLE</code>
     * @return a new PreparedStatement object containing the
     * pre-compiled SQL statement that will produce <code>ResultSet</code>
     * objects with the given type and concurrency
     * @exception SQLException if a database access error occurs
     *         or the given parameters are not <code>ResultSet</code> 
     *         constants indicating type and concurrency
     * @since 1.2
     */
    PreparedStatement prepareStatement(String sql, int resultSetType, 
				       int resultSetConcurrency)
	throws SQLException;

    /**
     * Creates a <code>CallableStatement</code> object that will generate
     * <code>ResultSet</code> objects with the given type and concurrency.
     * This method is the same as the <code>prepareCall</code> method
     * above, but it allows the default result set
     * type and concurrency to be overridden.
     *
     * @param sql a <code>String</code> object that is the SQL statement to
     *            be sent to the database; may contain on or more ? parameters
     * @param resultSetType a result set type; one of 
     *         <code>ResultSet.TYPE_FORWARD_ONLY</code>, 
     *         <code>ResultSet.TYPE_SCROLL_INSENSITIVE</code>, or
     *         <code>ResultSet.TYPE_SCROLL_SENSITIVE</code>
     * @param resultSetConcurrency a concurrency type; one of
     *         <code>ResultSet.CONCUR_READ_ONLY</code> or
     *         <code>ResultSet.CONCUR_UPDATABLE</code>
     * @return a new <code>CallableStatement</code> object containing the
     * pre-compiled SQL statement that will produce <code>ResultSet</code>
     * objects with the given type and concurrency
     * @exception SQLException if a database access error occurs
     *         or the given parameters are not <code>ResultSet</code> 
     *         constants indicating type and concurrency
     * @since 1.2
     */
    CallableStatement prepareCall(String sql, int resultSetType, 
				  int resultSetConcurrency) throws SQLException;

    /**
     * Retrieves the <code>Map</code> object associated with this 
     * <code>Connection</code> object.
     * Unless the application has added an entry, the type map returned 
     * will be empty.
     *
     * @return the <code>java.util.Map</code> object associated 
     *         with this <code>Connection</code> object
     * @exception SQLException if a database access error occurs
     * @since 1.2
     * @see #setTypeMap
     */
    java.util.Map getTypeMap() throws SQLException;

    /**
     * Installs the given <code>TypeMap</code> object as the type map for
     * this <code>Connection</code> object.  The type map will be used for the
     * custom mapping of SQL structured types and distinct types.
     *
     * @param map the <code>java.util.Map</code> object to install
     *        as the replacement for this <code>Connection</code>
     *        object's default type map
     * @exception SQLException if a database access error occurs or
     *        the given parameter is not a <code>java.util.Map</code> 
     *        object
     * @since 1.2
     * @see #getTypeMap
     */
    void setTypeMap(java.util.Map map) throws SQLException;

    //--------------------------JDBC 3.0-----------------------------


    /**
     * Changes the holdability of <code>ResultSet</code> objects
     * created using this <code>Connection</code> object to the given
     * holdability.
     *
     * @param holdability a <code>ResultSet</code> holdability constant; one of
     *        <code>ResultSet.HOLD_CURSORS_OVER_COMMIT</code> or
     *        <code>ResultSet.CLOSE_CURSORS_AT_COMMIT</code>
     * @throws SQLException if a database access occurs, the given parameter
     *         is not a <code>ResultSet</code> constant indicating holdability,
     *         or the given holdability is not supported
     * @see #getHoldability
     * @see ResultSet
     * @since 1.4
     */
    void setHoldability(int holdability) throws SQLException;

    /**
     * Retrieves the current holdability of <code>ResultSet</code> objects
     * created using this <code>Connection</code> object.
     *
     * @return the holdability, one of
     *        <code>ResultSet.HOLD_CURSORS_OVER_COMMIT</code> or
     *        <code>ResultSet.CLOSE_CURSORS_AT_COMMIT</code>
     * @throws SQLException if a database access occurs
     * @see #setHoldability
     * @see ResultSet
     * @since 1.4
     */
    int getHoldability() throws SQLException;

    /**
     * Creates an unnamed savepoint in the current transaction and 
     * returns the new <code>Savepoint</code> object that represents it.
     *
     * @return the new <code>Savepoint</code> object
     * @exception SQLException if a database access error occurs
     *            or this <code>Connection</code> object is currently in
     *            auto-commit mode
     * @see Savepoint
     * @since 1.4
     */
    Savepoint setSavepoint() throws SQLException;

    /**
     * Creates a savepoint with the given name in the current transaction
     * and returns the new <code>Savepoint</code> object that represents it.
     *
     * @param name a <code>String</code> containing the name of the savepoint
     * @return the new <code>Savepoint</code> object
     * @exception SQLException if a database access error occurs
     *            or this <code>Connection</code> object is currently in
     *            auto-commit mode
     * @see Savepoint
     * @since 1.4
     */
    Savepoint setSavepoint(String name) throws SQLException;

    /**
     * Undoes all changes made after the given <code>Savepoint</code> object
     * was set. 
     * <P>
     * This method should be used only when auto-commit has been disabled.
     *
     * @param savepoint the <code>Savepoint</code> object to roll back to
     * @exception SQLException if a database access error occurs,
     *            the <code>Savepoint</code> object is no longer valid,
     *            or this <code>Connection</code> object is currently in
     *            auto-commit mode
     * @see Savepoint
     * @see #rollback
     * @since 1.4
     */
    void rollback(Savepoint savepoint) throws SQLException;

    /**
     * Removes the given <code>Savepoint</code> object from the current 
     * transaction. Any reference to the savepoint after it have been removed 
     * will cause an <code>SQLException</code> to be thrown.
     *
     * @param savepoint the <code>Savepoint</code> object to be removed
     * @exception SQLException if a database access error occurs or
     *            the given <code>Savepoint</code> object is not a valid 
     *            savepoint in the current transaction
     * @since 1.4
     */
    void releaseSavepoint(Savepoint savepoint) throws SQLException;

    /**
     * Creates a <code>Statement</code> object that will generate
     * <code>ResultSet</code> objects with the given type, concurrency,
     * and holdability.
     * This method is the same as the <code>createStatement</code> method
     * above, but it allows the default result set
     * type, concurrency, and holdability to be overridden.
     *
     * @param resultSetType one of the following <code>ResultSet</code> 
     *        constants:
     *         <code>ResultSet.TYPE_FORWARD_ONLY</code>, 
     *         <code>ResultSet.TYPE_SCROLL_INSENSITIVE</code>, or
     *         <code>ResultSet.TYPE_SCROLL_SENSITIVE</code>
     * @param resultSetConcurrency one of the following <code>ResultSet</code> 
     *        constants:
     *         <code>ResultSet.CONCUR_READ_ONLY</code> or
     *         <code>ResultSet.CONCUR_UPDATABLE</code>
     * @param resultSetHoldability one of the following <code>ResultSet</code> 
     *        constants:
     *         <code>ResultSet.HOLD_CURSORS_OVER_COMMIT</code> or
     *         <code>ResultSet.CLOSE_CURSORS_AT_COMMIT</code>
     * @return a new <code>Statement</code> object that will generate
     *         <code>ResultSet</code> objects with the given type,
     *         concurrency, and holdability
     * @exception SQLException if a database access error occurs
     *            or the given parameters are not <code>ResultSet</code> 
     *            constants indicating type, concurrency, and holdability
     * @see ResultSet
     * @since 1.4
     */
    Statement createStatement(int resultSetType, int resultSetConcurrency, 
			      int resultSetHoldability) throws SQLException;

    /**
     * Creates a <code>PreparedStatement</code> object that will generate
     * <code>ResultSet</code> objects with the given type, concurrency,
     * and holdability.
     * <P>
     * This method is the same as the <code>prepareStatement</code> method
     * above, but it allows the default result set
     * type, concurrency, and holdability to be overridden.
     *
     * @param sql a <code>String</code> object that is the SQL statement to
     *            be sent to the database; may contain one or more ? IN
     *            parameters
     * @param resultSetType one of the following <code>ResultSet</code> 
     *        constants:
     *         <code>ResultSet.TYPE_FORWARD_ONLY</code>, 
     *         <code>ResultSet.TYPE_SCROLL_INSENSITIVE</code>, or
     *         <code>ResultSet.TYPE_SCROLL_SENSITIVE</code>
     * @param resultSetConcurrency one of the following <code>ResultSet</code> 
     *        constants:
     *         <code>ResultSet.CONCUR_READ_ONLY</code> or
     *         <code>ResultSet.CONCUR_UPDATABLE</code>
     * @param resultSetHoldability one of the following <code>ResultSet</code> 
     *        constants:
     *         <code>ResultSet.HOLD_CURSORS_OVER_COMMIT</code> or
     *         <code>ResultSet.CLOSE_CURSORS_AT_COMMIT</code>
     * @return a new <code>PreparedStatement</code> object, containing the
     *         pre-compiled SQL statement, that will generate
     *         <code>ResultSet</code> objects with the given type,
     *         concurrency, and holdability
     * @exception SQLException if a database access error occurs
     *            or the given parameters are not <code>ResultSet</code> 
     *            constants indicating type, concurrency, and holdability
     * @see ResultSet
     * @since 1.4
     */
    PreparedStatement prepareStatement(String sql, int resultSetType, 
				       int resultSetConcurrency, int resultSetHoldability)
	throws SQLException;

    /**
     * Creates a <code>CallableStatement</code> object that will generate
     * <code>ResultSet</code> objects with the given type and concurrency.
     * This method is the same as the <code>prepareCall</code> method
     * above, but it allows the default result set
     * type, result set concurrency type and holdability to be overridden.
     *
     * @param sql a <code>String</code> object that is the SQL statement to
     *            be sent to the database; may contain on or more ? parameters
     * @param resultSetType one of the following <code>ResultSet</code> 
     *        constants:
     *         <code>ResultSet.TYPE_FORWARD_ONLY</code>, 
     *         <code>ResultSet.TYPE_SCROLL_INSENSITIVE</code>, or
     *         <code>ResultSet.TYPE_SCROLL_SENSITIVE</code>
     * @param resultSetConcurrency one of the following <code>ResultSet</code> 
     *        constants:
     *         <code>ResultSet.CONCUR_READ_ONLY</code> or
     *         <code>ResultSet.CONCUR_UPDATABLE</code>
     * @param resultSetHoldability one of the following <code>ResultSet</code> 
     *        constants:
     *         <code>ResultSet.HOLD_CURSORS_OVER_COMMIT</code> or
     *         <code>ResultSet.CLOSE_CURSORS_AT_COMMIT</code>
     * @return a new <code>CallableStatement</code> object, containing the
     *         pre-compiled SQL statement, that will generate
     *         <code>ResultSet</code> objects with the given type,
     *         concurrency, and holdability
     * @exception SQLException if a database access error occurs
     *            or the given parameters are not <code>ResultSet</code> 
     *            constants indicating type, concurrency, and holdability
     * @see ResultSet
     * @since 1.4
     */
    CallableStatement prepareCall(String sql, int resultSetType, 
				  int resultSetConcurrency, 
				  int resultSetHoldability) throws SQLException;


    /**
     * Creates a default <code>PreparedStatement</code> object that has
     * the capability to retrieve auto-generated keys. The given constant
     * tells the driver whether it should make auto-generated keys
     * available for retrieval.  This parameter is ignored if the SQL 
     * statement is not an <code>INSERT</code> statement.
     * <P>
     * <B>Note:</B> This method is optimized for handling
     * parametric SQL statements that benefit from precompilation. If
     * the driver supports precompilation,
     * the method <code>prepareStatement</code> will send
     * the statement to the database for precompilation. Some drivers
     * may not support precompilation. In this case, the statement may
     * not be sent to the database until the <code>PreparedStatement</code> 
     * object is executed.  This has no direct effect on users; however, it does
     * affect which methods throw certain SQLExceptions.
     * <P>
     * Result sets created using the returned <code>PreparedStatement</code>
     * object will by default be type <code>TYPE_FORWARD_ONLY</code>
     * and have a concurrency level of <code>CONCUR_READ_ONLY</code>.
     *
     * @param sql an SQL statement that may contain one or more '?' IN
     *        parameter placeholders
     * @param autoGeneratedKeys a flag indicating whether auto-generated keys 
     *        should be returned; one of
     *        <code>Statement.RETURN_GENERATED_KEYS</code> or
     *	      <code>Statement.NO_GENERATED_KEYS</code>  
     * @return a new <code>PreparedStatement</code> object, containing the
     *         pre-compiled SQL statement, that will have the capability of
     *         returning auto-generated keys
     * @exception SQLException if a database access error occurs
     *         or the given parameter is not a <code>Statement</code>
     *         constant indicating whether auto-generated keys should be
     *         returned
     * @since 1.4
     */
    PreparedStatement prepareStatement(String sql, int autoGeneratedKeys)
	throws SQLException;

    /**
     * Creates a default <code>PreparedStatement</code> object capable
     * of returning the auto-generated keys designated by the given array.
     * This array contains the indexes of the columns in the target
     * table that contain the auto-generated keys that should be made
     * available. This array is ignored if the SQL 
     * statement is not an <code>INSERT</code> statement.
     * <P>
     * An SQL statement with or without IN parameters can be
     * pre-compiled and stored in a <code>PreparedStatement</code> object. This
     * object can then be used to efficiently execute this statement
     * multiple times.
     * <P>
     * <B>Note:</B> This method is optimized for handling
     * parametric SQL statements that benefit from precompilation. If
     * the driver supports precompilation,
     * the method <code>prepareStatement</code> will send
     * the statement to the database for precompilation. Some drivers
     * may not support precompilation. In this case, the statement may
     * not be sent to the database until the <code>PreparedStatement</code> 
     * object is executed.  This has no direct effect on users; however, it does
     * affect which methods throw certain SQLExceptions.
     * <P>
     * Result sets created using the returned <code>PreparedStatement</code>
     * object will by default be type <code>TYPE_FORWARD_ONLY</code>
     * and have a concurrency level of <code>CONCUR_READ_ONLY</code>.
     *
     * @param sql an SQL statement that may contain one or more '?' IN
     *        parameter placeholders
     * @param columnIndexes an array of column indexes indicating the columns
     *        that should be returned from the inserted row or rows 
     * @return a new <code>PreparedStatement</code> object, containing the
     *         pre-compiled statement, that is capable of returning the
     *         auto-generated keys designated by the given array of column
     *         indexes
     * @exception SQLException if a database access error occurs
     *
     * @since 1.4
     */
    PreparedStatement prepareStatement(String sql, int columnIndexes[])
	throws SQLException;

    /**
     * Creates a default <code>PreparedStatement</code> object capable
     * of returning the auto-generated keys designated by the given array.
     * This array contains the names of the columns in the target
     * table that contain the auto-generated keys that should be returned.
     * This array is ignored if the SQL 
     * statement is not an <code>INSERT</code> statement.
     * <P>
     * An SQL statement with or without IN parameters can be
     * pre-compiled and stored in a <code>PreparedStatement</code> object. This
     * object can then be used to efficiently execute this statement
     * multiple times.
     * <P>
     * <B>Note:</B> This method is optimized for handling
     * parametric SQL statements that benefit from precompilation. If
     * the driver supports precompilation,
     * the method <code>prepareStatement</code> will send
     * the statement to the database for precompilation. Some drivers
     * may not support precompilation. In this case, the statement may
     * not be sent to the database until the <code>PreparedStatement</code> 
     * object is executed.  This has no direct effect on users; however, it does
     * affect which methods throw certain SQLExceptions.
     * <P>
     * Result sets created using the returned <code>PreparedStatement</code>
     * object will by default be type <code>TYPE_FORWARD_ONLY</code>
     * and have a concurrency level of <code>CONCUR_READ_ONLY</code>.
     *
     * @param sql an SQL statement that may contain one or more '?' IN
     *        parameter placeholders
     * @param columnNames an array of column names indicating the columns
     *        that should be returned from the inserted row or rows 
     * @return a new <code>PreparedStatement</code> object, containing the
     *         pre-compiled statement, that is capable of returning the
     *         auto-generated keys designated by the given array of column
     *         names
     * @exception SQLException if a database access error occurs
     *
     * @since 1.4
     */
    PreparedStatement prepareStatement(String sql, String columnNames[])
	throws SQLException;


}