Re: UPDATE of partition key

On Thu, Sep 7, 2017 at 6:17 AM, Amit Khandekar <amitdkhan(dot)pg(at)gmail(dot)com> wrote:
> On 3 September 2017 at 17:10, Amit Khandekar <amitdkhan(dot)pg(at)gmail(dot)com> wrote:
>> After recent commit 30833ba154, now the partitions are expanded in
>> depth-first order. It didn't seem worthwhile rebasing my partition
>> walker changes onto the latest code. So in the attached patch, I have
>> removed all the partition walker changes. But
>> RelationGetPartitionDispatchInfo() traverses in breadth-first order,
>> which is different than the update result rels order (because
>> inheritance expansion order is depth-first). So, in order to make the
>> tuple-routing-related leaf partitions in the same order as that of the
>> update result rels, we would have to make changes in
>> RelationGetPartitionDispatchInfo(), which I am not sure whether it is
>> going to be done as part of the thread "expanding inheritance in
>> partition bound order" [1]. For now, in the attached patch, I have
>> reverted back to the hash table method to find the leaf partitions in
>> the update result rels.
>>
>> [1] https://www.postgresql.org/message-id/CAJ3gD9eyudCNU6V-veMme%2BeyzfX_ey%2BgEzULMzOw26c3f9rzdg%40mail.gmail.com
>
> As mentioned by Amit Langote in the above mail thread, he is going to
> do changes for making RelationGetPartitionDispatchInfo() return the
> leaf partitions in depth-first order. Once that is done, I will then
> remove the hash table method for finding leaf partitions in update
> result rels, and instead use the earlier efficient method that takes
> advantage of the fact that update result rels and leaf partitions are
> in the same order.

Has he posted that patch yet? I don't think I saw it, but maybe I
missed something.

--
Robert Haas
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