Re: [Semanticscuttle-devel] performance problem with mysql query

[Christian W. <cw...@cw...>]

Hello Eric,


> Mysql is using a file sort on one of the queries used to generate the
> homepage.... This is taking about 4 seconds of 100% cpu on my box...
> 
> I'm trying to optimize it, but don't have the required experience.
> 
> Here are the details:
> http://stackoverflow.com/questions/3722253/help-removing-mysql-file-sort

The query needs to be as follows:

SELECT U.username, B.*
 FROM sc_users AS U, sc_bookmarks AS B
 WHERE B.uId = U.uId AND B.bStatus = 0
 GROUP BY B.bModified DESC, B.bHash DESC
 ORDER BY B.bModified DESC
LIMIT 10

and you should create an index on status+modified+hash.

-- 
Regards/Mit freundlichen Grüßen
Christian Weiske

-=≡ Geeking around in the name of science since 1982 ≡=-