Hi, Pierre-Frédéric,
On Sat, 20 Nov 2004 17:12:43 +0100
Pierre-Frédéric Caillaud <[EMAIL PROTECTED]> wrote:
> > WHERE cd='ca' ORDER BY l_postcode;
>
> Write :
>
> > WHERE cd='ca' ORDER BY cd, l_postcode;
>
> You have a multicolumn index, so you should specify a multicolumn sort
> exactly the
Markus Schaber <[EMAIL PROTECTED]> writes:
> But as it fetches all the rows through the index, why doesn't it
> recognize that, fetching this way, the rows are already sorted by
> l_postcode?
Tell it to "ORDER BY cd, l_postcode".
> Is Postgresql 8 more intelligend in this case?
No.
Instead of :
WHERE cd='ca' ORDER BY l_postcode;
Write :
WHERE cd='ca' ORDER BY cd, l_postcode;
You have a multicolumn index, so you should specify a multicolumn sort
exactly the same as your index, and the planner will get it.
---(end of broadcast)
Hello,
I have the following query plan:
logigis=# explain SELECT geom, ref_in_id as ref, nref_in_id as nref, st_name as
name, substr(l_postcode,1,2) as postfirst, func_class as level FROM
schabi.streets WHERE cd='ca' ORDER BY l_postcode;
QUERY PLAN
