Re: UPDATE of partition key

On Thu, Jun 8, 2017 at 7:01 AM, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
> On Thu, Jun 8, 2017 at 1:33 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> On Wed, Jun 7, 2017 at 5:46 AM, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
>>> As far as I understand, it is to ensure that for deleted rows, nothing
>>> more needs to be done. For example, see the below check in
>>> ExecUpdate/ExecDelete.
>>> if (!ItemPointerEquals(tupleid, &hufd.ctid))
>>> {
>>> ..
>>> }
>>> ..
>>>
>>> Also a similar check in ExecLockRows. Now for deleted rows, if the
>>> t_ctid wouldn't point to itself, then in the mentioned functions, we
>>> were not in a position to conclude that the row is deleted.
>>
>> Right, so we would have to find all such checks and change them to use
>> some other method to conclude that the row is deleted. What method
>> would we use?
>
> I think before doing above check we can simply check if ctid.ip_blkid
> contains InvalidBlockNumber, then return an error.

Hmm, OK. That case never happens today?

--
Robert Haas
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