On Sun, Oct 11, 2009 at 3:30 PM, Michal Szymanski <mich20061@xxxxxxxxx> wrote:
We have similar problem and now we are try to find solution. When you
execute query on partion there is no sorting - DB use index to
retrieve data and if you need let say 50 rows it reads 50 rows using
index. But when you execute on parent table query optymizer do this:
it means 8544855 rows should be sorted and it takes long minutes.
-> Sort (cost=726844.88..748207.02 rows=8544855 width=37739)
(actual time=149864.868..149864.876 rows=50 loops=1)
The figures in first parenthesis are estimates, not the actual row count.
If you think it is too low, increase statistic target for that column.
We
have simpler situation than you and I will try to find solution
tommorow :)
Michal Szymanski
http://blog.szymanskich.net
http://techblog.freeconet.pl/
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GJ
