Hi,
On 2012-11-28 14:16:18 -0800, Christophe Pettus wrote:
> Thanks!
Not much to thank for, the answer was actually wrong...
> Does that apply to views as well? (This particular plan was not from a prepared or PL/pgSQL statement, but did
includeviews.)
Its not really relevant for views no.
The real answer for this is that this actually a 8.4 feature not the
aforementioned 9.2 feature.
The commit introducing this is:
http://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=bd3daddaf232d95b0c9ba6f99b0170a0147dd8af
What that does to add hashing support for IN(). But hashing can be
pessimal in comparison to a explicit check if only a few values come in,
so this can be checked at runtime after the above commit...
Greetings,
Andres Freund