Thanks Tom! I've never used the any function before. It totally fixed the issue. It's easier to code, makes more sense, and it fixed my performance issue.
My guess is that the optimizer does not how to deal with generate_subscripts??
Thanks!!
Anish
On Wed, Apr 13, 2011 at 9:15 AM, Tom Lane
<tgl@sss.pgh.pa.us> wrote:
Rob Sargent <
robjsargent@gmail.com> writes:
> On 04/13/2011 09:09 AM, Tom Lane wrote:
>> Anish Kejariwal<
anishkej@gmail.com> writes:
>>> (select store_id, avg(sales) sales
>>> from store
>>> where group_id in(select $1[i] from generate_subscripts($1, 1) g(i))
>> Seems like a pretty brute-force way to deal with the array. Try
>> where group_id = any($1)
>> Not sure if it'll be a great deal faster, but it's at least easier to
>> write.
> Would adding a subservient function which actually uses the value of the
> iteration (group_id) as a single parameter be of any use?
Well, it'd be unlikely to solve the OP's actual complaint, which was
performance. Hiding the semantics from the planner via a function
(which generally looks like a black box to the planner) is even worse
than hiding the semantics in a sub-SELECT, which I think is probably
the root cause of the performance issue here.
regards, tom lane