Re: partitioning

Did you set constraint_exclusion = true in postgresql.conf file?

On 12/13/05, Marc Cousin <mcousin(at)sigma(dot)fr> wrote:
> Hi,
>
> I've been working on trying to partition a big table (I've never partitioned a
> table in any other database till now).
> Everything went ok, except one query that didn't work afterwards.
>
> I've put the partition description, indexes, etc ..., and the explain plan
> attached.
>
> The query is extremely fast without partition (index scan backards on the
> primary key)
>
> The query is : "select * from logs order by id desc limit 100;"
> id is the primary key.
>
> It is indexed on all partitions.
>
> But the explain plan does full table scan on all partitions.
>
> While I think I understand why it is doing this plan right now, is there
> something that could be done to optimize this case ? Or put a warning in the
> docs about this kind of behaviour. I guess normally someone would partition
> to get faster queries :)
>
> Anyway, I thought I should mention this, as it has been quite a surprise.
>
>
>
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--
Regards
Pandu