Interfacing MySQL to Apache

It seems my attempt to post to the mysql general list has been silently rejected, or otherwise lost. It would probably be futile to speculate on what’s going on. If anyone reading this has the ear of the MySQL devs, perhaps you can draw their attention to it.

To: mysql@lists.mysql.com
Subject: Tying actions to (re)opening a connection
Date: Sat, 7 Jul 2007 10:44:05 +0100

The Apache DBD module maintains a dynamic pool of connections.

SQL statements may be defined at system startup. Such queries are then treated as prepared statements. In the MySQL driver, the sequence is:

    mysql_real_connect
    for each defined SQL statement {
        mysql_stmt_init
        mysql_stmt_prepare
    }

So far, so good. However, we also need to deal with connections that go stale. Our API defines a check_connection function. mysql_ping is *nearly* right for this, but unfortunately leaves us (silently) with a new connection without the prepared statements.

It would work perfectly if we could tie a callback to mysql_ping. Something like:

    int mysql_ping2(MYSQL *mysql,
                    int (*callback)(MYSQL*, void*),
                    void *dptr);

where the callback (if non-null) is invoked whenever mysql_ping detects a stale connection and reconnects.

Is this something you’d consider adding? Any other suggestions for a workaround to check the connection now?