On Wed, Feb 14, 2024 at 7:43 PM David G. Johnston < david.g.johns...@gmail.com> wrote:
> On Wednesday, February 14, 2024, Adam Fletcher <adamfblahb...@gmail.com> > wrote: >> >> >> Is it possible to get the parameterized prepared query inside an FDW such >> that it can be prepared/bind'd/execute'd on the receiving end of the FDW? >> >> For example, if I `PREPARE stmt(int) AS SELECT * from fdwrapped_tbl where >> pk = $1;` then `execute stmt(1);` I want my FDW be aware that the query was >> prepared. >> > > That isn’t how the separation of responsibilities works in PostgreSQL. > Execute is capable of producing a custom plan where instead of adding in > parameters and then planning around those unknowns the newly created plan > uses the supplied constants while planning. > > I do suspect that if a generic plan is chosen you will see the expected > parse nodes and can thus build a generic access plan to your foreign server > accordingly. > > You can control this for ease of testing via plan_cache_mode > > > https://www.postgresql.org/docs/current/runtime-config-query.html#GUC-PLAN-CACHE-MODE > Thanks David, this solved my problem - here’s the reasons I asked: https://github.com/EnterpriseDB/mysql_fdw/pull/293 - this adds parameter forwarding to the MySQL FDW. Thanks again! <https://www.postgresql.org/docs/current/runtime-config-query.html#GUC-PLAN-CACHE-MODE> >
