drupal/includes/database/mysql/database.inc

88 lines
2.7 KiB
PHP

<?php
// $Id$
/**
* @file
* Database interface code for MySQL database servers.
*/
/**
* @ingroup database
* @{
*/
class DatabaseConnection_mysql extends DatabaseConnection {
protected $transactionSupport;
public function __construct(Array $connection_options = array()) {
$connection_options += array(
'transactions' => FALSE,
'port' => 3306,
);
$this->transactionSupport = $connection_options['transactions'];
$dsn = 'mysql:host=' . $connection_options['host'] . ';port=' . $connection_options['port'] . ';dbname=' . $connection_options['database'];
parent::__construct($dsn, $connection_options['username'], $connection_options['password'], array(
// So we don't have to mess around with cursors and unbuffered queries by default.
PDO::MYSQL_ATTR_USE_BUFFERED_QUERY => TRUE,
// Because MySQL's prepared statements skip the query cache, because it's dumb.
PDO::ATTR_EMULATE_PREPARES => TRUE,
));
// Force MySQL to use the UTF-8 character set by default.
$this->exec('SET NAMES "utf8"');
// Enable MySQL's "strict mode", which removes most of MySQL's
// "just be lazy" behaviors that end up causing more trouble than they're worth.
$this->exec('SET sql_mode=STRICT_ALL_TABLES');
}
public function queryRange($query, Array $args, $from, $count, Array $options) {
// Backward compatibility hack, temporary.
$query = str_replace(array('%d' , '%f' , '%b' , "'%s'"), '?', $query);
return $this->query($query . ' LIMIT ' . $from . ', ' . $count, $args, $options);
}
public function queryTemporary($query, Array $args, $tablename, Array $options = array()) {
return $this->query(preg_replace('/^SELECT/i', 'CREATE TEMPORARY TABLE ' . $tablename . ' Engine=MEMORY SELECT', $query), $args, $options);
}
public function driver() {
return 'mysql';
}
public function databaseType() {
return 'mysql';
}
public function supportsTransactions() {
return $this->transactionSupport;
}
public function escapeTable($table) {
return preg_replace('/[^A-Za-z0-9_]+/', '', $table);
}
public function mapConditionOperator($operator) {
// We don't want to override any of the defaults.
return NULL;
}
/**
* @todo Remove this as soon as db_rewrite_sql() has been exterminated.
*/
public function distinctField($table, $field, $query) {
$field_to_select = 'DISTINCT(' . $table . '.' . $field . ')';
// (?<!text) is a negative look-behind (no need to rewrite queries that already use DISTINCT).
return preg_replace('/(SELECT.*)(?:' . $table . '\.|\s)(?<!DISTINCT\()(?<!DISTINCT\(' . $table . '\.)' . $field . '(.*FROM )/AUsi', '\1 ' . $field_to_select . '\2', $query);
}
}
/**
* @} End of "ingroup database".
*/