Re: MOVE strangeness

Tom Lane wrote:
> > This does not happen
> > if I replace the FETCHes by MOVEs.
>
> I'm a little confused by that remark; it seems to me that FETCH and MOVE
> have identical behaviors so far as repositioning the cursor is concerned.
> (Internally, MOVE *is* a FETCH, it just suppresses output of the rows.)
> Can you give an example where you get different behavior?

I think I see what Jeroen is saying. In this example he posted:

jtv=> begin;
BEGIN
jtv=> declare c cursor for select * from events;
DECLARE CURSOR
jtv=> fetch 3 in c;
year | event
------+------------------
2010 | A Space Oddyssey
2010 | Oddyssey Two
2038 | time_t overflow
(3 rows)

jtv=> move -3 in c;
MOVE 2

Why does the MOVE -3 return 2? If he has fetched 3, he is at the end of
the third row. If he does MOVE -3, hasn't he moved backward three rows
to the start of the first row?

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