Re: [HACKERS] UPDATE of partition key

On 20 December 2017 at 11:52, Amit Khandekar <amitdkhan(dot)pg(at)gmail(dot)com> wrote:
> On 14 December 2017 at 08:11, Amit Langote <Langote_Amit_f8(at)lab(dot)ntt(dot)co(dot)jp> wrote:
>>
>> Regarding ExecSetupChildParentMap(), it seems to me that it could simply
>> be declared as
>>
>> static void ExecSetupChildParentMap(ModifyTableState *mtstate);
>>
>> Looking at the places from where it's called, it seems that you're just
>> extracting information from mtstate and passing the same for the rest of
>> its arguments.
>
> Agreed. But the last parameter per_leaf might be necessary. I will
> defer this until I address Robert's concern about the complexity of
> the related code.

Removed those parameters, but kept perleaf. The map required for
update-tuple-routing is a per-subplan one despite the presence of
partition tuple routing. And we cannot deduce from mtstate whether
update tuple routing is true. So for this case, the caller has to
explicitly specify that per-subplan map has to be created.

>>
>> tupconv_map_for_subplan() looks like it could be done as a macro.
>
> Or may be inline function. I will again defer this for similar reason
> as the above deferred item about ExecSetupChildParentMap parameters.
>

Made it inline.

Did the above changes in attached update-partition-key_v33.patch

On 3 January 2018 at 11:42, Amit Khandekar <amitdkhan(dot)pg(at)gmail(dot)com> wrote:
> On 2 January 2018 at 10:56, David Rowley <david(dot)rowley(at)2ndquadrant(dot)com> wrote:
>> I'm pretty sure Robert is suggesting that
>> ExecSetupPartitionTupleRouting pallocs the memory for the structure,
>> sets it up then returns a pointer to the new struct. That's not very
>> unusual. It seems unusual for a function to return void and modify a
>> single parameter pointer to get the value to the caller rather than
>> just to return that value.
>
> Sorry, my mistake. Earlier I somehow was under the impression that the
> callers of ExecSetupPartitionTupleRouting() already have this
> structure palloc'ed, and that they pass address of this structure. I
> now can see that both CopyStateData->partition_tuple_routing and
> ModifyTableState->mt_partition_tuple_routing are pointers, not
> structures. So it make perfect sense for
> ExecSetupPartitionTupleRouting() to palloc and return a pointer. Sorry
> for the noise. Will share the change in an upcoming patch version.
> Thanks !

ExecSetupPartitionTupleRouting() now returns PartitionTupleRouting *.

Did this change in v3 version of
0001-Encapsulate-partition-related-info-in-a-structure.patch

--
Thanks,
-Amit Khandekar
EnterpriseDB Corporation
The Postgres Database Company