Re: [HACKERS] Enhanced containment selectivity function - Mailing list pgsql-patches

From Matteo Beccati
Subject Re: [HACKERS] Enhanced containment selectivity function
Date
Msg-id 44644100.2090705@beccati.com
Whole thread Raw
In response to Re: [HACKERS] Enhanced containment selectivity function  (Bruce Momjian <pgman@candle.pha.pa.us>)
Responses Re: [HACKERS] Enhanced containment selectivity function
List pgsql-patches
Hi,

Bruce Momjian ha scritto:
> Uh, I just moved the selectivity function over to /contrib/ltree, and
> moved what I needed, so it now works.  You can continue with the plan
> above, or I can.

I've just been able to install a 8.2-devel to test the ltree selectivity
  improvements I suggested.

It was a big surprise having no improvements at all in the query I used
for all my previous tests, until I found out that the test against
histogram values was removed by Tom. I strongly think it should be
reintroduced: ltree columns are likely to have a unique constraint and
the current ltreeparentsel function will behave just like contsel in
these cases.

Here is the commit:

> Log Message:
> -----------
> Fix ltreeparentsel so it actually works ...
>
> Modified Files:
> --------------
>     pgsql/contrib/ltree:
>         ltree_op.c (r1.10 -> r1.11)
>         (http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/ltree/ltree_op.c.diff?r1=1.10&r2=1.11)
>


Best regards
--
Matteo Beccati
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