public static Db open(DataSource ds){
  try {
    return new Db(ds.getConnection());
  }
 catch (  SQLException e) {
    throw convert(e);
  }
}

public static Db open ( DataSource ds ) { try { return new Db ( ds . getConnection ( ) ) ; } catch ( SQLException e ) { throw convert ( e ) ; } }
create a new database instance using a data source . this method is fast , so that you can always call open ( ) / close ( ) on usage .
