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From Dan Armbrust <daniel.armbrust.l...@gmail.com>
Subject Re: performance, memory consumption...and a big hello :)
Date Wed, 29 Jul 2009 13:37:59 GMT
> Problem 1:
>
> select id_group, count(id)
> group by id_group
>
> This takes a couple of minutes,

Is that the entire query?  No where clause?

I don't think any database is going to use the index when you aren't
providing a where clause... especially when you have a count and a
group by in there... it has to read the entire table.

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