Re: Posible planner improvement?

>>> On Mon, May 26, 2008 at  6:30 AM, ITAGAKI Takahiro
<itagaki.takahiro@oss.ntt.co.jp> wrote:
> Albert Cervera Areny <albert@sedifa.com> wrote:
>
>> I've got a query similar to this:
>>
>> select * from t1, t2 where t1.id > 158507 and t1.id = t2.id;
>>
>> That took > 84 minutes (the query was a bit longer but this is the
part that
>> made the difference) after a little change the query took ~1
second:
>>
>> select * from t1, t2 where t1.id > 158507 and t2.id > 158507 and
t1.id =
>> t2.id;
>
> I had a similar problem here:
>   http://archives.postgresql.org/pgsql-general/2007-02/msg00850.php
> and added a redundant inequality explicitly to make it work well.
>
> I think it is worth trying to improve, but I'm not sure we can do it
> against user defined types. Does postgres always require transitive
law
> to all types?

I've recently run into this.  It would be a nice optimization,
if feasible.

-Kevin