Horton

Re: UPDATE of partition key

Etsuro Fujita <fujita.etsuro@lab.ntt.co.jp>

View thread View on postgr.es
From: Etsuro Fujita <fujita.etsuro@lab.ntt.co.jp>
To: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>, Robert Haas <robertmhaas@gmail.com>, Amit Khandekar <amitdkhan.pg@gmail.com>
Cc: Amit Kapila <amit.kapila16@gmail.com>, Dilip Kumar <dilipbalaut@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2017-07-04T08:25:17Z
Lists: pgsql-hackers 
On 2017/07/03 18:54, Amit Langote wrote:
> On 2017/07/02 20:10, Robert Haas wrote:

>> But that seems like it wouldn't be too hard to fix: let's have
>> expand_inherited_rtentry() expand the partitioned table in the same
>> order that will be used by ExecSetupPartitionTupleRouting().

That's really what I wanted when updating the patch for tuple-routing to 
foreign partitions.  (I don't understand the issue discussed here, though.)

>> That
>> seems pretty easy to do - just have expand_inherited_rtentry() notice
>> that it's got a partitioned table and call
>> RelationGetPartitionDispatchInfo() instead of find_all_inheritors() to
>> produce the list of OIDs.
Seems like a good idea.

> Interesting idea.
> 
> If we are going to do this, I think we may need to modify
> RelationGetPartitionDispatchInfo() a bit or invent an alternative that
> does not do as much work.  Currently, it assumes that it's only ever
> called by ExecSetupPartitionTupleRouting() and hence also generates
> PartitionDispatchInfo objects for partitioned child tables.  We don't need
> that if called from within the planner.
> 
> Actually, it seems that RelationGetPartitionDispatchInfo() is too coupled
> with its usage within the executor, because there is this comment:
> 
>          /*
>           * We keep the partitioned ones open until we're done using the
>           * information being collected here (for example, see
>           * ExecEndModifyTable).
>           */

Yeah, we need some refactoring work.  Is anyone working on that?

Best regards,
Etsuro Fujita

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.