Re: cursors FOR UPDATE don't return most recent row

Excerpts from Tom Lane's message of sáb ene 28 01:35:33 -0300 2012:
> Alvaro Herrera <alvherre@alvh.no-ip.org> writes:
> > I expected the FETCH to return one row, with the latest data, i.e.
> > (1, 3), but instead it's returning empty.
>
> This is the same thing I was complaining about in the bug #6123 thread,
> http://archives.postgresql.org/message-id/9698.1327266271@sss.pgh.pa.us
>
> It looks a bit ticklish to fix.

Hm.  Okay, I hadn't read that.

In my FOR KEY SHARE patch I have added a heap_lock_updated_tuple that
makes heap_lock_tuple follow the update chain forward when the tuple
being locked is being updated by a concurrent transaction.  I haven't
traced through FETCH to see if it makes sense to apply some of that to
it.

--
Álvaro Herrera <alvherre@commandprompt.com>
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