Horton

Re: Declarative partitioning - another take

Amit Langote <langote_amit_f8@lab.ntt.co.jp>

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From: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
To: Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>
Cc: Robert Haas <robertmhaas@gmail.com>, Amit Langote <amitlangote09@gmail.com>, Rajkumar Raghuwanshi <rajkumar.raghuwanshi@enterprisedb.com>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2016-11-15T09:51:42Z
Lists: pgsql-hackers 
On 2016/11/11 20:49, Ashutosh Bapat wrote:
> I have not looked at the latest set of patches, but in the version
> that I have we create one composite type for every partition. This
> means that if there are thousand partitions, there will be thousand
> identical entries in pg_type. Since all the partitions share the same
> definition (by syntax), it doesn't make sense to add so many identical
> entries. Moreover, in set_append_rel_size(), while translating the
> expressions from parent to child, we add a ConvertRowtypeExpr instead
> of whole-row reference if reltype of the parent and child do not match
> (adjust_appendrel_attrs_mutator())
>                    if (appinfo->parent_reltype != appinfo->child_reltype)
>                     {
>                         ConvertRowtypeExpr *r = makeNode(ConvertRowtypeExpr);
> 
> I guess, we should set reltype of child to that of parent for
> declarative partitions.

Thanks for the suggestion.  I agree that partitions having the same
reltype as the parent will help a number of cases including the one you
mentioned, but I haven't yet considered how invasive such a change will be.

Thanks,
Amit

Commits

  1. Fix typo.

  2. Document trigger-firing behavior for inheritance/partitioning.

  3. Fire per-statement triggers on partitioned tables.

  4. Set ecxt_scantuple correctly for tuple routing.

  5. Fix interaction of partitioned tables with BulkInsertState.

  6. Avoid core dump for empty prepared statement in an aborted transaction.

  7. Fix some problems in check_new_partition_bound().

  8. Remove unnecessary arguments from partitioning functions.

  9. Fix reporting of constraint violations for table partitioning.

  10. Fix tuple routing in cases where tuple descriptors don't match.

  11. Invalid parent's relcache after CREATE TABLE .. PARTITION OF.

  12. Doc: improve documentation about inheritance.