Re: Optimising "in" queries

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.

Filter: (sensor_id = ANY ('{1137,1138,1139,1140}'::integer[]))

I've never seen this plan item except for when array's are involved.  I
could be wrong.  I'd like to know how this is generated when you don't
have an array.

Regards

Russell Smith