public function diff($schema, $parse = true)
    {
        // prepare
        if ($parse) {
            $this->getParser()->parse($schema);
        }

        // output container for rescued SQL query
        $queries = [];

        // loop throu the schema
        foreach ($schema as $table => &$attributes) {
            $table = $parse ? $this->getPrefix($table) : $table;
            $query = $this->diffTable($table, $attributes, false);

            if (count($query) > 0) {
                $queries = array_merge($queries, $query);
            }
        }

        return $queries;
    }