"Guillaume Bog" <[EMAIL PROTECTED]> writes:
> I have performance issues if I do the following pseudo-query:
> SELECT a, b, (SELECT count(*) FROM t2 WHERE something) AS c
> FROM t1 ORDER BY a LIMIT 10;
> After some tests, it seems to me that the subquery on t2 is computed for all
> rows of t1.
Ye
am Tue, dem 25.11.2008, um 16:44:34 +0800 mailte Guillaume Bog folgendes:
> It seems that you are right. By further testing I found that a WHERE condition
> in the subquery was making the query hundred times slower. As I'm not very
> familiar with explain analyze, I paste them below. Why do I have
On Tue, Nov 25, 2008 at 15:56, A. Kretschmer <
[EMAIL PROTECTED]> wrote:
> am Tue, dem 25.11.2008, um 15:34:57 +0800 mailte Guillaume Bog folgendes:
> > Hi dear Postgres users.
> >
> > I have performance issues if I do the following pseudo-query:
> >
> > SELECT a, b, (SELECT count(*) FROM t2 WHER
am Tue, dem 25.11.2008, um 15:34:57 +0800 mailte Guillaume Bog folgendes:
> Hi dear Postgres users.
>
> I have performance issues if I do the following pseudo-query:
>
> SELECT a, b, (SELECT count(*) FROM t2 WHERE something) AS c
> FROM t1 ORDER BY a LIMIT 10;
>
> After some tests, it seems to
Hi dear Postgres users.
I have performance issues if I do the following pseudo-query:
SELECT a, b, (SELECT count(*) FROM t2 WHERE something) AS c
FROM t1 ORDER BY a LIMIT 10;
After some tests, it seems to me that the subquery on t2 is computed for all
rows of t1. As I don't "ORDER BY c", there i
