On Fri, Nov 6, 2009 at 1:02 AM, Les Mikesell <lesmikesell at gmail.com> wrote: > Rudi Ahlers wrote: > >>>>>> What else could cause this kind of problem? >>>>> You only have 449MB free on /tmp. It could easily fill that up during the >>>>> query, and then delete the file before you run df again. Run it while the >>>>> query is executing, I bet you see /tmp filling up. >>>>> >>>> Thanx, that seems to have solved the problem. I didn't think of >>>> checking to see if the tmp folder got full during the SQL statement >>>> execution. So, by increasing it to 1GB, the problem is solved > >>> I've seen mysql do dumb stuff like building a huge temp table in a 3-way >>> join before evaluating any of the WHEN clause that would eliminate most >>> of it, but does it really have to make a copy of a single table to pick >>> a random chunk? >>> > >> >> This could very well be the case. The website in question is written >> in PERL (yea, I know.....) and the client doesn't really pay much for >> us to look into the code to see if it can be optimized either. So I >> just have to make sure the VPS copes with it. But for now it's working >> fine :) > > > There's nothing inherently wrong with perl for web programming and it > doesn't have anything at all to do with the query passed to mysql. > There are some quirks with apache/mod_perl that might matter for > efficiency, though. > > -- > Les Mikesell > lesmikesell at gmail.com > _______________________________________________ well, let me put it this way ( I should have said it in the previous email), the code was written about 6 years ago, and the developer has since "dissapeared", so it's old & outdated. PERL is good, I agree, but PERL programmers are few and far apart where we are, so it's a bit of a pain to keep up. -- Kind Regards Rudi Ahlers CEO, SoftDux Hosting Web: http://www.SoftDux.com Office: 087 805 9573 Cell: 082 554 7532