/**
* Method to initialize a transaction.
*
* @param boolean $asSavepoint If true and a transaction is already active, a savepoint will be created.
*
* @return void
*
* @since 1.0
* @throws \RuntimeException
*/
public function transactionStart($asSavepoint = false)
{
$this->connect();
if (!$asSavepoint || !$this->transactionDepth) {
parent::transactionStart($asSavepoint);
} else {
$savepoint = 'SP_' . $this->transactionDepth;
$this->setQuery('SAVEPOINT ' . $this->quoteName($savepoint));
if ($this->execute()) {
$this->transactionDepth++;
}
}
}