Re: [MonetDB-users] sql filter slow

On Wed, Jan 28, 2009 at 02:21:37PM -0500, Chris Curvey wrote:

On Wed, Jan 28, 2009 at 11:47 AM, dariuszs wrote:

...

Hi, If I rewrite this query like this

select * from (select gender,count(*) from table1 group by gender) as t1 where t1.gender in ('F','M');

It takes about 2 seconds which is wonderful however how do I apply this to very complicated queries? Thanks. Dariusz.

I might suggest that it will be cleaner to do it this way.

select gender, count(*) from table1 group by gender having gender in ('F','M');

(In the past, I've found that the construct "select ... from (select ....)" ends up creating SQL that's really hard to debug. YMMV.)

indeed a good idea --- [cs]hould have been mine ... ;-) dariuszs, feel free to test/trace this one on your data, too. Stefan

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