Re: cursor sensitivity misunderstanding

On Thu, Feb 18, 2021 at 9:00 AM Peter Eisentraut <
peter.eisentraut@enterprisedb.com> wrote:

>
> And that seems definitely wrong.  Declaring c1 in the above example as
> FOR UPDATE or FOR SHARE does not change the result.  I think this
> discussion is mixing up the concept of cursor sensitivity with
> transaction isolation.
>
> Thoughts?
>
>
This came up on Discord in the context of pl/pgsql last month - never
really came to a conclusion.

"
open curs FOR SELECT * FROM Res FOR UPDATE;
    LOOP
        FETCH curs into record;
        EXIT WHEN NOT FOUND;
        INSERT INTO Res SELECT Type.Name
                        FROM Type
                        WHERE Type.SupClass = record.Name;
    END LOOP;
"

The posted question was: "this doesn't go over rows added during the loop
despite the FOR UPDATE"

The OP was doing a course based on Oracle and was confused regarding our
behavior.  The documentation failed to help me provide a useful response,
so I'd agree there is something here that needs reworking if not outright
fixing.

David J.