/**
* gets an instance of this class
*
* @static
* @access public
* @return Object, System_Database_Connection
*/
public static function getInstance()
{
if (!self::$_instance) {
self::$_instance = new self();
}
return self::$_instance;
}
/**
* gets a connection to the database and sets it to the _db property
*
* @param string $connection_name, name of the connection to get
* @access public
* @return object, System_Database_Base
*/
public function getConnection($connection_name)
{
$this->_db = System_Database_Connection::getInstance()->getConnection($connection_name);
return $this;
}
/**
* creates the commit query based on the object registrations
*
* @access public
* @return boolean status of the transaction
*/
public function commit()
{
/**
* gather all of the queries
*/
$this->buildNew()->buildDirty()->buildRemoved();
$committed = false;
$count = count($this->_query_stack);
$transaction_stack = $this->_query_stack;
ksort($transaction_stack);
/**
* get the current db being used
*/
$db = System_Database_Connection::getInstance()->getConnection('default');
/**
* check for errors, if so set the return to false and do not process any queries
* check to see if the transaction_stack has any queries. if none set the return to false and process none
* if no errors, loop through the transaction_stack and run each query
* if the query fails, run the ROLLBACK query, set the return to false, and break the loop
* if all of the queries execute fine, run a COMMIT query to commit the transaction
* run the reset method no matter what happens
*/
if ($this->_errors || !$count) {
$committed = false;
} else {
$db->runQuery('START TRANSACTION');
$iter = 0;
foreach ($transaction_stack as $group) {
$rollback = false;
$query = $group['query'];
$query_type = $group['type'];
if (is_object($query)) {
$query->{$query_type}()->run();
if ($query->error()) {
$rollback = true;
}
} elseif (is_string($query)) {
$db->runQuery($query);
if ($db->error()) {
$rollback = true;
}
}
if ($rollback) {
$db->runQuery('ROLLBACK');
$committed = false;
break;
} else {
$iter++;
}
}
if ($iter == $count) {
$db->runQuery('COMMIT');
$committed = true;
}
}
$this->reset();
return $committed;
}