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eFaps is a framework used to map objects with or without attached files to a relational database and optional file systems (only for attaches files). Configurable access control can be provided down to object and attribute level depending on implementation and use case. Depending on requirements, events (like triggers) allow to implement business logic and to separate business logic from user interface. The framework includes integrations (e.g. webdav, full text search) and a web application as 'simple' configurable user interface. Some best practises, example web application modules (e.g. team work module) support administrators and implementers using this framework.

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/*
 * Copyright 2003 - 2011 The eFaps Team
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * Revision:        $Rev: 6210 $
 * Last Changed:    $Date: 2011-02-18 16:02:56 -0500 (Fri, 18 Feb 2011) $
 * Last Changed By: $Author: [email protected] $
 */

package org.efaps.db.databases;

import java.sql.Connection;
import java.sql.SQLException;

/**
 * The database driver is used for Oracle databases starting with version 9i.
 * The difference to {@link OracleDatabase} is, that this class supports auto
 * generated keys.
 *
 * @author The eFaps Team
 * @version $Id: OracleDatabaseWithAutoSequence.java 6210 2011-02-18 21:02:56Z [email protected] $
 */
public class OracleDatabaseWithAutoSequence
    extends OracleDatabase
{
    /**
     * For the database from vendor Oracle, an eFaps SQL table with
     * auto increment is created in this steps:
     * 
     * SQL table itself with column ID and unique key on the
     *     column is created
     * sequence with same name of table and suffix _SEQ is
     *     created
     * trigger with same name of table and suffix _TRG is
     *     created. The trigger sets automatically the column ID
     *     with the next value of the sequence
     * 
     * An eFaps SQL table without auto increment, but with parent table is
     * created in this steps:
     * 
     * SQL table itself with column ID and unique key on the
     *     column is created
     * the foreign key to the parent table is automatically set
     * 
     * The creation of the table itself is done by calling the inherited method
     * {@link OracleDatabase#createTable}
     *
     * @param _con            SQL connection
     * @param _table          name of the table to create
     * @param _parentTable    name of the parent table
     * @return this vendor specific DB definition
     * @throws SQLException if trigger could not be created
     * @see OracleDatabase#createTable(Connection, String, String)
     */
/* TODO
    @Override()
    public OracleDatabaseWithAutoSequence createTable(final Connection _con,
                                                      final String _table,
                                                      final String _parentTable)
        throws SQLException
    {
        super.createTable(_con, _table, _parentTable);

        if (_parentTable == null)  {
            final Statement stmt = _con.createStatement();

            try  {
                // create trigger for auto increment
                final StringBuilder cmd = new StringBuilder()
                    .append("create trigger ").append(_table).append("_TRG")
                    .append("  before insert on ").append(_table)
                    .append("  for each row ")
                    .append("begin")
                    .append("  select ").append(_table).append("_SEQ.nextval ")
                    .append("      into :new.ID from dual;")
                    .append("end;");
                stmt.executeUpdate(cmd.toString());
            } finally  {
                stmt.close();
            }
        }
        return this;
    }
*/
    /**
     * This implementation of the vendor specific database driver implements
     * the auto generated keys. So always true is returned.
     *
     * @return always true because supported by Oracle database
     */
    @Override()
    public boolean supportsGetGeneratedKeys()
    {
        return true;
    }

    /**
     * @return always true because supported by Oracle database
     */
    @Override()
    public boolean supportsMultiGeneratedKeys()
    {
        return true;
    }

  /**
   * This method normally returns for given table and column a new id. Because
   * this database driver support auto generated keys, an SQL exception is
   * always thrown.
   *
   * @param _con          sql connection
   * @param _table        sql table for which a new id must returned
   * @param _column       sql table column for which a new id must returned
   * @return nothing, because SQLException is always thrown
   * @throws SQLException always, because this database driver supports auto
   *                      generating keys
   */
    @Override()
    public long getNewId(final Connection _con,
                         final String _table,
                         final String _column)
        throws SQLException
    {
        throw new SQLException("The database driver uses auto generated keys and "
                               + "a new id could not returned without making "
                               + "a new insert.");
    }
}