Many thanks Alec. I need to wait a couple of hours before I can block access to the DB by messing with the indexes, but I will try out what you suggest. What you say makes sense as probably over 99% of the values in that first col will be 'y'. I will post my progress. I am also looking into recoding the where clause as inner joins ... I didn;t expect this to make any difference as I would have thought mysql figures this out but it _seems_ to cut down the query time to 2-3 secs without using any extra index columns ... bizarre. But I'll take what I can get.
Answering questions definitely gets answers ... there is a pithy aphorism in there somewhere ... :) Jim > > PS I am answering loads of questions in the hope that the power of my > Karma > > will force someone to answer mine ... (join problem:indexed columns being > > ignored) > > My first reaction would be to turn your index round. Something with > settings of "y" and "n" is going to make a rotten index, especially as the > first part. It is possible that MySQL will look at that part of it, decide > that this is a lousy index, and ditch it. If you put the diffuse part of > the index first, then the boolean, it might sort better. I don't think you > have to change your query - I think MySQL is savvy enough to commute over > the AND. (This email has been scanned for viruses by www.emf-systems.com) -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
