Обсуждение: postgres_fdw : disable extended queries
Hello,
I have a 9.6 pg instance, and I am trying to link a foreign postgresql database that do not accept extended queries. (only simple queries https://www.postgresql.org/docs/current/static/protocol.html )
When I run a query against the foreign pg instance thought postres_fdw, it looks like it sends a transaction containing
DECLARE c1 CURSOR FOR
SELECT customer_id FROM foodmart.customer
SELECT customer_id FROM foodmart.customer
-> is there a way to run a simple query with postgres_fdw such:
SELECT customer_id FROM foodmart.customer
Thanks,
Nicolas Paris wrote: > I have a 9.6 pg instance, and I am trying to link a foreign postgresql database that do not accept > extended queries. (only simple queries https://www.postgresql.org/docs/current/static/protocol.html ) > > When I run a query against the foreign pg instance thought postres_fdw, it looks like it sends a > transaction containing > > DECLARE c1 CURSOR FOR > SELECT customer_id FROM foodmart.customer > > -> is there a way to run a simple query with postgres_fdw such: > > SELECT customer_id FROM foodmart.customer No, it is part of the design that cursors are used, so that rows can be fetched one at a time and concurrent DML statements can be run. You might consider using dblink. Yours, Laurenz Albe
2016-10-24 10:36 GMT+02:00 Albe Laurenz <laurenz.albe@wien.gv.at>:
Nicolas Paris wrote:
> I have a 9.6 pg instance, and I am trying to link a foreign postgresql database that do not accept
> extended queries. (only simple queries https://www.postgresql.org/docs/current/static/protocol. html )
>
> When I run a query against the foreign pg instance thought postres_fdw, it looks like it sends a
> transaction containing
>
> DECLARE c1 CURSOR FOR
> SELECT customer_id FROM foodmart.customer
>
> -> is there a way to run a simple query with postgres_fdw such:
>
> SELECT customer_id FROM foodmart.customer
No, it is part of the design that cursors are used, so that rows can be
fetched one at a time and concurrent DML statements can be run.
Actually problem is not with the cursor, sorry. Error message says it's related to a prepared statement.
I am not able to debug it and see what is happening and what is the prepared statement.
You might consider using dblink.
Dblink works great, but It seems less flexible (no predicate push down). I am able to create a view that encapsulate dblink, but all the rows are fetch each time I use the view.
Dblink works great, but It seems less flexible (no predicate push down). I am able to create a view that encapsulate dblink, but all the rows are fetch each time I use the view.
Yours,
Laurenz Albe