Interesting semantics. I have never seen the IN syntax referred to as
"array processing" before.
I have always thought of array processing as the thing that vector
processors such as Cray and ETA do/did.
While superficially equivalent, I have always believed that IN (a,b,c)
executed faster than =a or =b or =c. Am I wrong for PostgreSQL?
Stephen
On Wednesday 22 August 2007 22:55, Michael Glaesemann wrote:
> On Aug 22, 2007, at 5:58 , Russell Smith wrote:
> > Stephen Davies wrote:
> >> select count(rdate),rdate from reading where sensor_id in
> >> (1137,1138,1139,1140) group by rdate order by rdate desc limit 1;
> >
> > It would have been helpful to see the table definition here. I can
> > say up front that array processing in postgres is SLOW.
>
> Um, what array processing are you seeing here? IN (a, b, b) is not an
> array construct.
>
> Michael Glaesemann
> grzm seespotcode net
--
========================================================================
This email is for the person(s) identified above, and is confidential to
the sender and the person(s). No one else is authorised to use or
disseminate this email or its contents.
Stephen Davies Consulting Voice: 08-8177 1595
Adelaide, South Australia. Fax: 08-8177 0133
Computing & Network solutions. Mobile:0403 0405 83
