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;BEGINjtv=> declare c cursor for select *
fromevents;DECLARE CURSORjtv=> 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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