Hi there! Today i had a look at drupal.org's slow query log after I found out it is collecting data. Note that the slow query log now also contains queries that don't use an index, no matter how fast. There were 2 queries responsible for about 2/3 of the entries. One is the query from drupal_is_denied, which is run on each bootstrap. This query has been improved for Drupal 5, but I think it coul dbe further approved by doing away with the two LOWER()s in there in case you just check an IP. The other one was the harmless looking query: SELECT * FROM files f INNER JOIN file_revisions r ON f.fid = r.fid WHERE r.vid = 38515 ORDER BY f.fid; an EXPLAIN revealed that it did not use any index. The reason is that we have defined its index as PRIMARY KEY (fid, vid). Chris Johnson explained: vid is a constant, and we are ordering the resulting fids. But in a composite key, MySQL cannot use (at least in version 4.x) any of the components of the composite key if the first component is not used. So what I did is to switch the keys around: alter table file_revisions drop primary key, add primary key (vid, fid); Somebody might want to roll a patch or Drupal5. Cheers, Gerhard