Last week, my colleague Massimo and I discussed how to handle big result sets coming from MySQL in Python. The problem is that MySQL doesn't support server-side cursors, so you need to select everything and then read it. You can do it either buffered or not. MySQL Connector/Python defaults to non-buffered, meaning that you need to fetch all rows after issuing a SELECT statement. You can also turn on the buffering, mimicking what MySQL for Python (MySQLdb) does.

For big result sets, it's better to limit your search. You can do this using an integer primary key or some temporal field for example. Or you can use the LIMIT keyword. The latter solution is what

Latest code of MySQL Connector/Python on launchpad has support for multiple result sets when you execute a stored procedure. We also changed the way the actual result of the routine is returned to conform to PEP249.

Here is some example code: it creates a stored procedure which generates 2 result sets. You can get the result by calling next_resultset(), which is returning a MySQLCursorBuffered.

    cur = cnx.cursor()

    cur.execute("DROP PROCEDURE IF EXISTS multi")
    proc = """
      CREATE PROCEDURE multi(IN pFac1 INT, IN pFac2 INT, OUT pProd INT)
      BEGIN
        SELECT 1,'a' as FooBar;
        SELECT 2;
        SET pProd := pFac1 * pFac2;