framework/mutex/OracleMutex.php
protected function releaseLock($name)
    {
        $releaseStatus = null;
        $this->db->useMaster(function ($db) use ($name, &$releaseStatus) {
            /** @var \yii\db\Connection $db */
            $db->createCommand(
                'DECLARE
    handle VARCHAR2(128);
BEGIN
    DBMS_LOCK.ALLOCATE_UNIQUE(:name, handle);
    :result := DBMS_LOCK.RELEASE(handle);
END;',
                [':name' => $name]
            )
            ->bindParam(':result', $releaseStatus, PDO::PARAM_INT, 1)
            ->execute();
        });

        return $releaseStatus === 0 || $releaseStatus === '0';
    }
protected function releaseLock($name)
    {
        $releaseStatus = null;
        $this->db->useMaster(function ($db) use ($name, &$releaseStatus) {
            /** @var \yii\db\Connection $db */
            $db->createCommand(
                'DECLARE
    handle VARCHAR2(128);
BEGIN
    DBMS_LOCK.ALLOCATE_UNIQUE(:name, handle);
    :result := DBMS_LOCK.RELEASE(handle);
END;',
                [':name' => $name]
            )
            ->bindParam(':result', $releaseStatus, PDO::PARAM_INT, 1)
            ->execute();
        });

        return $releaseStatus === 0 || $releaseStatus === '0';
    }
Releases lock by given name.
@param string $name of the lock to be released.
@return bool release result.
@see http://docs.oracle.com/cd/B19306_01/appdev.102/b14258/d_lock.htm