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From:Gmail User Date:May 22 2007 6:34pm
Subject:Re: Upgraded to 5.0.x from 4.1.x and ORDER BY sucks!
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> possible you had set up some query cache in 4, but not currently in 5?

may not be optimized, but yes, query cache is enabled, all 25 MB of it. :-)

> how did you 'upgraded' your data?

regrettably, in-place.

interestingly, I was recovering after server crash that chopped of a
table. after upgrading the server (in-place), I re-read the corrupt
table from script dumped by mysqlbinlog. it is THAT table that is
causing me grief. I thought it was some missing indices, but I have
indices on all columns I use in WHERE.

> what means this exactly?
> in reverse ordered tables, query is fast on second or on first table order?

'select ... from table1, table2, table3 ... order by table1.column'  is FAST

'select ... from table1, table2, table3 ... order by table2.column' is SLOW


> did your tried an EXPLAIN?

yes, thanks for reminding me to use it. I compared the two; the slow
one uses temporary table and filesort; the fast one does not. Both use
where and all select types are SIMPLE.

So, with your help, I know why it is slow. Is there a way to out of
this without downgrading the server?
Thread
Upgraded to 5.0.x from 4.1.x and ORDER BY sucks!Gmail User22 May
  • Re: Upgraded to 5.0.x from 4.1.x and ORDER BY sucks!Sebastian Mendel22 May
    • Re: Upgraded to 5.0.x from 4.1.x and ORDER BY sucks!Gmail User22 May
  • Re: Upgraded to 5.0.x from 4.1.x and ORDER BY sucks!David Sparks22 May
    • Re: Upgraded to 5.0.x from 4.1.x and ORDER BY sucks!Gmail User24 May
re: Upgraded to 5.0.x from 4.1.x and ORDER BY sucks!J.R. Bullington22 May
  • Re: Upgraded to 5.0.x from 4.1.x and ORDER BY sucks!Gmail User22 May