Re: Expression errors with "FOR UPDATE" and postgres_fdw with partition wise join enabled.

On Mon, Jul 9, 2018 at 4:33 PM, Etsuro Fujita
<fujita.etsuro@lab.ntt.co.jp> wrote:
>>
>>
>> As I said, we do spend cycles in that function testing whether a node
>> is Aggref or not even when the query doesn't have aggregates or
>> grouping OR spend cycles in testing whether a node is a PlaceHolderVar
>> when the query doesn't produce any. So, I don't see any problem with
>> spending a few cycles testing whether a node is ConvertRowtypeExpr or
>> not when a ConvertRowtypeExpr is not in the query or command. That's
>> not a huge performance trouble. I would be happy to change my mind, if
>> you show me performance different with and without this patch in
>> planning. I haven't seen any.
>
>
> I have to admit that the case in [1] wouldn't affect the performance, but my
> concern is that there might be some cases where the test affects
> performance.

What are those cases? Can you please provide any numbers supporting your claim?

-- 
Best Wishes,
Ashutosh Bapat
EnterpriseDB Corporation
The Postgres Database Company