code: public static function statement(Database $database, $table, $key)
      {
          $statement = $database->getMasterLink()->prepare('ALTER TABLE ' . $table . ' DROP CONSTRAINT IF EXISTS fk_' . $key);
  
          return $statement;
      }
docs: Prepare and return according PDO statement.
  
  @param  Database     $database database
  @param  string       $table    table name
  @param  string       $key      foreign key name
  @return \PDOStatement $statement prepared query