[mythtv-users] Slow MySQL query after delete

Tom Dexter digitalaudiorock at gmail.com
Tue Sep 4 05:32:34 UTC 2007

On 9/3/07, crs23 wrote:
> So your query took 0.02 seconds and it was the actual query, not the
> 'EXPLAIN' query?

I just tried that SQL on my system.  In my case it only returned 63
rows, so it's not much of a test.  In any case, it was pretty much
instantaneous...0.18 seconds.

I've done quite a bit of application development with MySQL, and the
performance you describe is a bit strange.  My experience has been
that, on any reasonably fast system, even with very complex joins that
require table scans (where no index is used) performance is usually
very good even when tables contain 50,000 or 100,000+ rows.  That
query should be pretty trivial even on a really bloated myth box.

As others have suggested, I'd run that optimize_mythdb.pl script and
see if it helps.  If that doesn't help I'm not sure what to
suggest...possibly something is really slowing down disk access to the
database files (??).


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