mysqli.php

Joomla!是一套获得过多个奖项的内容管理系统(Content Management System, CMS)。Joomla!采用PHP+MySQL数据库开发

<?php
/**
* @version		$Id: mysqli.php 11316 2008-11-27 03:11:24Z ian $
* @package		Joomla.Framework
* @subpackage	Database
* @copyright	Copyright (C) 2005 - 2008 Open Source Matters. All rights reserved.
* @license		GNU/GPL, see LICENSE.php
* Joomla! is free software. This version may have been modified pursuant
* to the GNU General Public License, and as distributed it includes or
* is derivative of works licensed under the GNU General Public License or
* other free or open source software licenses.
* See COPYRIGHT.php for copyright notices and details.
*/

// Check to ensure this file is within the rest of the framework
defined('JPATH_BASE') or die();

/**
 * MySQLi database driver
 *
 * @package		Joomla.Framework
 * @subpackage	Database
 * @since		1.0
 */
class JDatabaseMySQLi extends JDatabase
{
	/**
	 *  The database driver name
	 *
	 * @var string
	 */
	var $name			= 'mysqli';

	/**
	 * The null/zero date string
	 *
	 * @var string
	 */
	var $_nullDate		= '0000-00-00 00:00:00';

	/**
	 * Quote for named objects
	 *
	 * @var string
	 */
	var $_nameQuote		= '`';

	/**
	* Database object constructor
	*
	* @access	public
	* @param	array	List of options used to configure the connection
	* @since	1.5
	* @see		JDatabase
	*/
	function __construct( $options )
	{
		$host		= array_key_exists('host', $options)	? $options['host']		: 'localhost';
		$user		= array_key_exists('user', $options)	? $options['user']		: '';
		$password	= array_key_exists('password',$options)	? $options['password']	: '';
		$database	= array_key_exists('database',$options)	? $options['database']	: '';
		$prefix		= array_key_exists('prefix', $options)	? $options['prefix']	: 'jos_';
		$select		= array_key_exists('select', $options)	? $options['select']	: true;

		// Unlike mysql_connect(), mysqli_connect() takes the port and socket
		// as separate arguments. Therefore, we have to extract them from the
		// host string.
		$port	= NULL;
		$socket	= NULL;
		$targetSlot = substr( strstr( $host, ":" ), 1 );
		if (!empty( $targetSlot )) {
			// Get the port number or socket name
			if (is_numeric( $targetSlot ))
				$port	= $targetSlot;
			else
				$socket	= $targetSlot;

			// Extract the host name only
			$host = substr( $host, 0, strlen( $host ) - (strlen( $targetSlot ) + 1) );
			// This will take care of the following notation: ":3306"
			if($host == '')
				$host = 'localhost';
		}

		// perform a number of fatality checks, then return gracefully
		if (!function_exists( 'mysqli_connect' )) {
			$this->_errorNum = 1;
			$this->_errorMsg = 'The MySQL adapter "mysqli" is not available.';
			return;
		}

		// connect to the server
		if (!($this->_resource = @mysqli_connect($host, $user, $password, NULL, $port, $socket))) {
			$this->_errorNum = 2;
			$this->_errorMsg = 'Could not connect to MySQL';
			return;
		}

		// finalize initialization
		parent::__construct($options);

		// select the database
		if ( $select ) {
			$this->select($database);
		}
	}

	/**
	 * Database object destructor
	 *
	 * @return boolean
	 * @since 1.5
	 */
	function __destruct()
	{
		$return = false;
		if (is_resource($this->_resource)) {
			$return = mysqli_close($this->_resource);
		}
		return $return;
	}

	/**
	 * Test to see if the MySQLi connector is available
	 *
	 * @static
	 * @access public
	 * @return boolean  True on success, false otherwise.
	 */
	function test()
	{
		return (function_exists( 'mysqli_connect' ));
	}

	/**
	 * Determines if the connection to the server is active.
	 *
	 * @access	public
	 * @return	boolean
	 * @since	1.5
	 */
	function connected()
	{
		return $this->_resource->ping();
	}

	/**
	 * Select a database for use
	 *
	 * @access	public
	 * @param	string $database
	 * @return	boolean True if the database has been successfully selected
	 * @since	1.5
	 */
	function select($database)
	{
		if ( ! $database )
		{
			return false;
		}

		if ( !mysqli_select_db($this->_resource, $database)) {
			$this->_errorNum = 3;
			$this->_errorMsg = 'Could not connect to database';
			return false;
		}

		// if running mysql 5, set sql-mode to mysql40 - thereby circumventing strict mode problems
		if ( strpos( $this->getVersion(), '5' ) === 0 ) {
			$this->setQuery( "SET sql_mode = 'MYSQL40'" );
			$this->query();
		}

		return true;
	}

	/**
	 * Determines UTF support
	 *
	 * @access public
	 * @return boolean True - UTF is supported
	 */
	function hasUTF()
	{
		$verParts = explode( '.', $this->getVersion() );
		return ($verParts[0] == 5 || ($verParts[0] == 4 && $verParts[1] == 1 && (int)$verParts[2] >= 2));
	}

	/**
	 * Custom settings for UTF support
	 *
	 * @access public
	 */
	function setUTF()
	{
		mysqli_query( $this->_resource, "SET NAMES 'utf8'" );
	}

	/**
	 * Get a database escaped string
	 *
	 * @param	string	The string to be escaped
	 * @param	boolean	Optional parameter to provide extra escaping
	 * @return	string
	 * @access	public
	 * @abstract
	 */
	function getEscaped( $text, $extra = false )
	{
		$result = mysqli_real_escape_string( $this->_resource, $text );
		if ($extra) {
			$result = addcslashes( $result, '%_' );
		}
		return $result;
	}
	/**
	* Execute the query
	*
	* @access public
	* @return mixed A database resource if successful, FALSE if not.
	*/
	function query()
	{
		if (!is_object($this->_resource)) {
			return false;
		}

		// Take a local copy so that we don't modify the original query and cause issues later
		$sql = $this->_sql;
		if ($this->_limit > 0 || $this->_offset > 0) {
			$sql .= ' LIMIT '.$this->_offset.', '.$this->_limit;
		}
		if ($this->_debug) {
			$this->_ticker++;
			$this->_log[] = $sql;
		}
		$this->_errorNum = 0;
		$this->_errorMsg = '';
		$this->_cursor = mysqli_query( $this->_resource, $sql );

		if (!$this->_cursor)
		{
			$this->_errorNum = mysqli_errno( $this->_resource );
			$this->_errorMsg = mysqli_error( $this->_resource )." SQL=$sql";

			if ($this->_debug) {
				JError::raiseError(500, 'JDatabaseMySQL::query: '.$this->_errorNum.' - '.$this->_errorMsg );
			}
			return false;
		}
		return $this->_cursor;
	}

	/**
	 * Description
	 *
	 * @access public
	 * @return int The number of affected rows in the previous operation
	 * @since 1.0.5
	 */
	function getAffectedRows()
	{
		return mysqli_affected_rows( $this->_resource );
	}

	/**
	* Execute a batch query
	*
	* @access public
	* @return mixed A database resource if successful, FALSE if not.
	*/
	function queryBatch( $abort_on_error=true, $p_transaction_safe = false)
	{
		$this->_errorNum = 0;
		$this->_errorMsg = '';
		if ($p_transaction_safe) {
			$this->_sql = rtrim($this->_sql, "; \t\r\n\0");
			$si = $this->getVersion();
			preg_match_all( "/(\d+)\.(\d+)\.(\d+)/i", $si, $m );
			if ($m[1] >= 4) {
				$this->_sql = 'START TRANSACTION;' . $this->_sql . '; COMMIT;';
			} else if ($m[2] >= 23 && $m[3] >= 19) {
				$this->_sql = 'BEGIN WORK;' . $this->_sql . '; COMMIT;';
			} else if ($m[2] >= 23 && $m[3] >= 17) {
				$this->_sql = 'BEGIN;' . $this->_sql . '; COMMIT;';
			}
		}
		$query_split = $this->splitSql($this->_sql);
		$error = 0;
		foreach ($query_split as $command_line) {
			$command_line = trim( $command_line );
			if ($command_line != '') {
				$this->_cursor = mysqli_query( $this->_resource, $command_line );
				if ($this->_debug) {
					$this->_ticker++;
					$this->_log[] = $command_line;
				}
				if (!$this->_cursor) {
					$error = 1;
					$this->_errorNum .= mysqli_errno( $this->_resource ) . ' ';
					$this->_errorMsg .= mysqli_error( $this->_resource )." SQL=$command_line <br />";
					if ($abort_on_error) {
						return $this->_cursor;
					}
				}
			}
		}
		return $error ? false : true;
	}

	/**
	 * Diagnostic function
	 *
	 * @access public
	 * @return	string
	 */
	function explain()
	{
		$temp = $this->_sql;
		$this->_sql = "EXPLAIN $this->_sql";

		if (!($cur = $this->query())) {
			return null;
		}
		$first = true;

		$buffer = '<table id="explain-sql">';
		$buffer .= '<thead><tr><td colspan="99">'.$this->getQuery().'</td></tr>';
		while ($row = mysqli_fetch_assoc( $cur )) {
			if ($first) {
				$buffer .= '<tr>';
				foreach ($row as $k=>$v) {
					$buffer .= '<th>'.$k.'</th>';
				}
				$buffer .= '</tr>';
				$first = false;
			}
			$buffer .= '</thead><tbody><tr>';
			foreach ($row as $k=>$v) {
				$buffer .= '<td>'.$v.'</td>';
			}
			$buffer .= '</tr>';
		}
		$buffer .= '</tbody></table>';
		mysqli_free_result( $cur );

		$this->_sql = $temp;

		return $buffer;
	}

	/**
	 * Description
	 *
	 * @access public