On Jul 26, 2006, at 4:45 AM, Gerhard Killesreiter wrote:

Since last night, I let the devel module collect query statistics on drupal.org. We now can see which queries are run very often and which are just slow.

Great! If I can get a copy of the Drupal.org schema then I'll write the EXPLAINs for both these queries and the Slow queries from the Drupal.org databases. We just need a PHP Snippet that puts an EXPLAIN in front of these queries and converts INSERTS, UPDATES, and DELETES to SELECTS to use EXPLAINs.

I'll then ask for the snippet to be run on Drupal.org by a maintainer with PHP Input format privileges so I can review the EXPLAINS. It's also worth noting that Peter Zaitsev, the MySQL performance lead, has been explaining how MySQL EXPLAIN can be wrong here: http://www.mysqlperformanceblog.com/2006/07/24/mysql-explain-limits-and-errors/

Cheers,

Kieran