Re: [GENERAL] Two questions about join performance

Well maybe now is a good time to take a look at your
design and see why you have to do this.
There just happens to be a number of great DBAs on
this list as well. :-)

Rudy

On 6 Aug 99, at 2:14, Roberto Moreda wrote:

> Sorry for being so reiterative :)
>
> The planifier isn't perfect for many queries...
> Is there any way (without touch C code) to tell explicitly the plan of a
> query to Postgres?
>
> How can I manage the problem of select a few rows with a boolean atribute
> when they are 5 rows in a table of 100000 rows? I't must to be an index,
> but the optimizer asumes that a Seq Scan is more cheap... yes, yes... I
> know : if I ask for the 100000 then Seq Scan is the solution, but the
> interesting query is the other : to extract the 5 rows with flag='Y' from
> whitin the 100000 rows with the flag='N'.
>
> I'm in a big trouble because of all this.
>
> TIA again.
>
>  Roberto
>
> --
> Roberto Moreda
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