/branches/RunPolitics_576/system/database/drivers/odbc/odbc_driver.php

<?php  if (!defined('BASEPATH')) exit('No direct script access allowed');

/**

 * CodeIgniter

 *

 * An open source application development framework for PHP 4.3.2 or newer

 *

 * @package		CodeIgniter

 * @author		Rick Ellis

 * @copyright	Copyright (c) 2006, EllisLab, Inc.

 * @license		http://www.codeignitor.com/user_guide/license.html

 * @link		http://www.codeigniter.com

 * @since		Version 1.0

 * @filesource

 */



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



/**

 * ODBC Database Adapter Class

 *

 * Note: _DB is an extender class that the app controller

 * creates dynamically based on whether the active record

 * class is being used or not.

 *

 * @package		CodeIgniter

 * @subpackage	Drivers

 * @category	Database

 * @author		Rick Ellis

 * @link		http://www.codeigniter.com/user_guide/database/

 */

class CI_DB_odbc_driver extends CI_DB {



	/**

	 * Non-persistent database connection

	 *

	 * @access	private called by the base class

	 * @return	resource

	 */	

	function db_connect()

	{

		return @odbc_connect($this->hostname, $this->username, $this->password);

	}

	

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



	/**

	 * Persistent database connection

	 *

	 * @access	private called by the base class

	 * @return	resource

	 */	

	function db_pconnect()

	{

		return @odbc_pconnect($this->hostname, $this->username, $this->password);

	}

	

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



	/**

	 * Select the database

	 *

	 * @access	private called by the base class

	 * @return	resource

	 */	

	function db_select()

	{

		// Not needed for ODBC

		return TRUE;

	}



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



	/**

	 * Version number query string

	 *

	 * @access	public

	 * @return	string

	 */

	function _version()

	{

		return "SELECT version() AS ver";

	}



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



	/**

	 * Execute the query

	 *

	 * @access	private called by the base class

	 * @param	string	an SQL query

	 * @return	resource

	 */	

	function _execute($sql)

	{

		$sql = $this->_prep_query($sql);

		return @odbc_exec($this->conn_id, $sql);

	}

	

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



	/**

	 * Prep the query

	 *

	 * If needed, each database adapter can prep the query string

	 *

	 * @access	private called by execute()

	 * @param	string	an SQL query

	 * @return	string

	 */	

	function _prep_query($sql)

	{

		return $sql;

	}



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



	/**

	 * Begin Transaction

	 *

	 * @access	public

	 * @return	bool		

	 */	

	function trans_begin($test_mode = FALSE)

	{

		if ( ! $this->trans_enabled)

		{

			return TRUE;

		}

		

		// When transactions are nested we only begin/commit/rollback the outermost ones

		if ($this->_trans_depth > 0)

		{

			return TRUE;

		}



		// Reset the transaction failure flag.

		// If the $test_mode flag is set to TRUE transactions will be rolled back

		// even if the queries produce a successful result.

		$this->_trans_failure = ($test_mode === TRUE) ? TRUE : FALSE;



		return odbc_autocommit($this->conn_id, FALSE);

	}



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



	/**

	 * Commit Transaction

	 *

	 * @access	public

	 * @return	bool		

	 */	

	function trans_commit()

	{

		if ( ! $this->trans_enabled)

		{

			return TRUE;

		}



		// When transactions are nested we only begin/commit/rollback the outermost ones

		if ($this->_trans_depth > 0)

		{

			return TRUE;

		}



		$ret = odbc_commit($this->conn_id);

		odbc_autocommit($this->conn_id, TRUE);

		return $ret;

	}



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



	/**

	 * Rollback Transaction

	 *

	 * @access	public

	 * @return	bool		

	 */	

	function trans_rollback()

	{

		if ( ! $this->trans_enabled)

		{

			return TRUE;

		}



		// When transactions are nested we only begin/commit/rollback the outermost ones

		if ($this->_trans_depth > 0)

		{

			return TRUE;

		}



		$ret = odbc_rollback($this->conn_id);

		odbc_autocommit($this->conn_id, TRUE);

		return $ret;

	}



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



	/**

	 * Escape String

	 *

	 * @access	public

	 * @param	string

	 * @return	string

	 */

	function escape_str($str)	

	{

		// ODBC doesn't require escaping

		return $str;

	}

	

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



	/**

	 * Affected Rows

	 *

	 * @access	public

	 * @return	integer

	 */

	function affected_rows()

	{

		return @odbc_num_rows($this->conn_id);

	}

	

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



	/**

	 * Insert ID

	 *

	 * @access	public

	 * @return	integer

	 */

	function insert_id()

	{

		return @odbc_insert_id($this->conn_id);

	}



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



	/**

	 * "Count All" query

	 *

	 * Generates a platform-specific query string that counts all records in

	 * the specified database

	 *

	 * @access	public

	 * @param	string

	 * @return	string

	 */

	function count_all($table = '')

	{

		if ($table == '')

			return '0';

	

		$query = $this->query("SELECT COUNT(*) AS numrows FROM `".$this->dbprefix.$table."`");

		

		if ($query->num_rows() == 0)

			return '0';



		$row = $query->row();

		return $row->numrows;

	}



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



	/**

	 * Show table query

	 *

	 * Generates a platform-specific query string so that the table names can be fetched

	 *

	 * @access	private

	 * @return	string

	 */

	function _list_tables()

	{

		return "SHOW TABLES FROM `".$this->database."`";		

	}

	

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



	/**

	 * Show column query

	 *

	 * Generates a platform-specific query string so that the column names can be fetched

	 *

	 * @access	public

	 * @param	string	the table name

	 * @return	string

	 */

	function _list_columns($table = '')

	{

		return "SHOW COLUMNS FROM ".$this->_escape_table($table);

	}



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



	/**

	 * Field data query

	 *

	 * Generates a platform-specific query so that the column data can be retrieved

	 *

	 * @access	public

	 * @param	string	the table name

	 * @return	object

	 */

	function _field_data($table)

	{

		return "SELECT TOP 1 FROM ".$this->_escape_table($table);

	}



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



	/**

	 * The error message string

	 *

	 * @access	private

	 * @return	string

	 */

	function _error_message()

	{

		return odbc_errormsg($this->conn_id);

	}

	

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



	/**

	 * The error message number

	 *

	 * @access	private

	 * @return	integer

	 */

	function _error_number()

	{

		return odbc_error($this->conn_id);

	}

	

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



	/**

	 * Escape Table Name

	 *

	 * This function adds backticks if the table name has a period

	 * in it. Some DBs will get cranky unless periods are escaped

	 *

	 * @access	private

	 * @param	string	the table name

	 * @return	string

	 */

	function _escape_table($table)

	{

		if (stristr($table, '.'))

		{

			$table = preg_replace("/\./", "`.`", $table);

		}

		

		return $table;

	}

		

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



	/**

	 * Insert statement

	 *

	 * Generates a platform-specific insert string from the supplied data

	 *

	 * @access	public

	 * @param	string	the table name

	 * @param	array	the insert keys

	 * @param	array	the insert values

	 * @return	string

	 */

	function _insert($table, $keys, $values)

	{	

		return "INSERT INTO ".$this->_escape_table($table)." (".implode(', ', $keys).") VALUES (".implode(', ', $values).")";

	}

	

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



	/**

	 * Update statement

	 *

	 * Generates a platform-specific update string from the supplied data

	 *

	 * @access	public

	 * @param	string	the table name

	 * @param	array	the update data

	 * @param	array	the where clause

	 * @return	string

	 */

	function _update($table, $values, $where)

	{

		foreach($values as $key => $val)

		{

			$valstr[] = $key." = ".$val;

		}

	

		return "UPDATE ".$this->_escape_table($table)." SET ".implode(', ', $valstr)." WHERE ".implode(" ", $where);

	}

	

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



	/**

	 * Delete statement

	 *

	 * Generates a platform-specific delete string from the supplied data

	 *

	 * @access	public

	 * @param	string	the table name

	 * @param	array	the where clause

	 * @return	string

	 */	

	function _delete($table, $where)

	{

		return "DELETE FROM ".$this->_escape_table($table)." WHERE ".implode(" ", $where);

	}



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



	/**

	 * Limit string

	 *

	 * Generates a platform-specific LIMIT clause

	 *

	 * @access	public

	 * @param	string	the sql query string

	 * @param	integer	the number of rows to limit the query to

	 * @param	integer	the offset value

	 * @return	string

	 */

	function _limit($sql, $limit, $offset)

	{

		// Does ODBC doesn't use the LIMIT clause?

		return $sql;

	}



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



	/**

	 * Close DB Connection

	 *

	 * @access	public

	 * @param	resource

	 * @return	void

	 */

	function _close($conn_id)

	{

		@odbc_close($conn_id);

	}



	

}





?>