Horton

Re: [HACKERS] UPDATE of partition key

Amit Khandekar <amitdkhan.pg@gmail.com>

View thread View on postgr.es
From: Amit Khandekar <amitdkhan.pg@gmail.com>
To: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
Cc: Robert Haas <robertmhaas@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>, Thomas Munro <thomas.munro@enterprisedb.com>
Date: 2017-11-27T08:28:57Z
Lists: pgsql-hackers 
On 24 November 2017 at 10:52, Amit Langote
<Langote_Amit_f8@lab.ntt.co.jp> wrote:
> On 2017/11/23 21:57, Amit Khandekar wrote:
>> If we collect the partition keys in expand_partitioned_rtentry(), we
>> need to pass the root relation also, so that we can convert the
>> partition key attributes to root rel descriptor. And the other thing
>> is, may be, we can check beforehand (in expand_inherited_rtentry)
>> whether the rootrte's updatedCols is empty, which I think implies that
>> it's not an UPDATE operation. If yes, we can just skip collecting the
>> partition keys.
>
> Yeah, it seems like a good idea after all to check in
> expand_inherited_rtentry() whether the root RTE's updatedCols is non-empty
> and if so check if any of the updatedCols are partition keys.  If we find
> some, then it will suffice to just set a simple flag in the
> PartitionedChildRelInfo that will be created for the root table.  That
> should be done *after* we have visited all the tables in the partition
> tree including some that might be partitioned and hence will provide their
> partition keys.  The following block in expand_inherited_rtentry() looks
> like a good spot:
>
>         if (rte->inh && partitioned_child_rels != NIL)
>         {
>             PartitionedChildRelInfo *pcinfo;
>
>             pcinfo = makeNode(PartitionedChildRelInfo);

Yes, I am thinking about something like that. Thanks.

I am also working on your suggestion of moving the
convert-to-root-descriptor logic from ExecInsert() to ExecUpdate().

So, in the upcoming patch version, I am intending to include the above
two, and if possible, Robert's idea of re-using is_partition_attr()
for pull_child_partition_columns().


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

Commits

  1. Avoid referencing off the end of subplan_partition_offsets.

  2. Allow UPDATE to move rows between partitions.

  3. Remove useless lookup of root partitioned rel in ExecInitModifyTable().

  4. Factor error generation out of ExecPartitionCheck.

  5. Minor preparatory refactoring for UPDATE row movement.

  6. Simplify and encapsulate tuple routing support code.

  7. Avoid coercing a whole-row variable that is already coerced.

  8. Use ResultRelInfo ** rather than ResultRelInfo * for tuple routing.

  9. Make RelationGetPartitionDispatchInfo expand depth-first.

  10. Expand partitioned tables in PartDesc order.

  11. Use a real RT index when setting up partition tuple routing.

  12. Fix transition tables for partition/inheritance.

  13. Fix confusion about number of subplans in partitioned INSERT setup.

  14. Prevent BEFORE triggers from violating partitioning constraints.

  15. Fire per-statement triggers on partitioned tables.

  16. Fix reporting of violations in ExecConstraints, again.

  17. Don't scan partitioned tables.

  18. Allow FDWs to push down quals without breaking EvalPlanQual rechecks.