My post didn't go through the first time, so here goes again:
>
>
> I thought I read somewhere that it was better to avoid using
> the IN clause (at least when that means doing a subselect)
> for efficiency reasons, but I cannot find it on the website now.
>
> Does anyone know where that is?
>
> And can someone confirm the following:
>
> This:
> SELECT t1.f1
> FROM t1
> WHERE t1.f1 IN (select f1 from t2 AS t2 where t2.f1 = t1.f1
> AND t2.f2 = 'v1')
>
> is generally slower to run then:
> SELECT t1.f1
> FROM t1, t2
> WHERE t1.f1 = t2.f1
> AND t2.f3 = 'v1'
>
> Thanks
>
> Terry Fielder
> Network Engineer
> Great Gulf Homes / Ashton Woods Homes
> terry(at)greatgulfhomes(dot)com
>
>