Re: UPDATE of partition key

Amit Kapila <amit.kapila16@gmail.com>

From: Amit Kapila <amit.kapila16@gmail.com>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Simon Riggs <simon@2ndquadrant.com>, Amit Khandekar <amitdkhan.pg@gmail.com>, Greg Stark <stark@mit.edu>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2017-05-18T03:43:55Z
Lists: pgsql-hackers
 On Wed, May 17, 2017 at 5:17 PM, Robert Haas <robertmhaas@gmail.com> wrote:
> On Wed, May 17, 2017 at 6:29 AM, Amit Kapila <amit.kapila16@gmail.com> wrote:
>> I think we can do this even without using an additional infomask bit.
>> As suggested by Greg up thread, we can set InvalidBlockId in ctid to
>> indicate such an update.
>
> Hmm.  How would that work?
>

We can pass a flag say row_moved (or require_row_movement) to
heap_delete which will in turn set InvalidBlockId in ctid instead of
setting it to self. Then the ExecUpdate needs to check for the same
and return an error when heap_update is not successful (result !=
HeapTupleMayBeUpdated).  Can you explain what difficulty are you
envisioning?

-- 
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com


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.