> Releases before 7.4 are spotty about supporting backwards scan of
> complex queries --- if you have a join or aggregate in the query,
> it likely won't work, yielding either strange errors or wrong answers.
>
> It will work if the top plan node in the query is a SORT, though, so
> a possible workaround is to add an explicit ORDER BY to the cursor's
> query. (You will need to do some investigation with EXPLAIN to make
> sure you are getting a suitable plan for the cursor.)
I rewrote my query to have sort in top of plan:
Sort (cost=151.24..151.25 rows=1 width=36) Sort Key: czas -> Aggregate (cost=151.22..151.23 rows=1 width=36)
-> Group (cost=151.22..151.23 rows=1 width=36) -> Sort (cost=151.22..151.22 rows=1 width=36)
I'm not sure if it is what you were talking about, but it didn't help.
Anyway the best choice for this function would be a C function, but SPI
scares me...
And one more question - which syntax is valid?
move backward..
or
execute ''move backward...
> Or try 7.4 beta ...
Currently stable branches are better for me...
>
> regards, tom lane
Regards,
Tomasz Myrta
