Re: An issue in remote query optimization

On 2017/01/31 19:53, Abbas Butt wrote:
> On Tue, Jan 31, 2017 at 2:25 AM, Etsuro Fujita
> <fujita(dot)etsuro(at)lab(dot)ntt(dot)co(dot)jp <mailto:fujita(dot)etsuro(at)lab(dot)ntt(dot)co(dot)jp>> wrote:
> On 2017/01/31 18:24, Abbas Butt wrote:

> Postgres_fdw optimizes remote queries by pushing down the where
> clause.
> This feature does not work consistently when the query is
> executed from
> within a pl/pgsql function. The optimization works when the function
> executes the query for the first 5 times, and fails afterwards.

> I understand that this is because PostgreSQL starts using
> generic plan
> with pulled up where clause after the 5th invocation hoping that it
> would be faster since we have skiped planning the query on each
> invocation, but in this case this decision is causing the query
> to slow
> down.

> How should we fix this problem?

> ANALYZE for the foreign table doesn't work?

> No.
>
> analyze ts.tickets;
> WARNING: skipping "tickets" --- cannot analyze this foreign table
> ANALYZE

How the foreign table ts.tickets is defined?

Best regards,
Etsuro Fujita