Thread

Re: Add SPLIT PARTITION/MERGE PARTITIONS commands

Tender Wang <tndrwang@gmail.com> — 2025-12-21T07:14:01Z

Alexander Korotkov <aekorotkov@gmail.com> 于2025年12月20日周六 19:08写道：

> Hi Tender,
>
> On Sat, Dec 20, 2025 at 5:18 AM Tender Wang <tndrwang@gmail.com> wrote:
> > I found this feature merged; thanks for this work.
> > I tested it and found that one place in the error errcode may need to be
> changed.
> > In checkPartition():
> > ...
> > if (get_partition_parent(partRelOid, false) != RelationGetRelid(rel))
> >     ereport(ERROR,
> >     errcode(ERRCODE_UNDEFINED_TABLE),
> >     errmsg("relation \"%s\" is not a partition of relation \"%s\"",
> > ...
> >
> > ERRCODE_UNDEFINED_TABLE usually means "table does not exist."
> > When entering here, the table should exist, otherwise table_open()
> already reports an error.
> > I found another two errcode in checkPartition() use
> ERRCODE_WRONG_OBJECT_TYPE,
> > In the attached patch, I replace ERRCODE_UNDEFINED_TABLE with
> ERRCODE_WRONG_OBJECT_TYPE.
>
> I agree with you that ERRCODE_UNDEFINED_TABLE is certainly wrong error
> code because the table actually exists.  ERRCODE_WRONG_OBJECT_TYPE is
> better.  For example, we throw it when trying to attach a partition to
> non-partitioned table.  So, the parent table type is wrong.  However,
> are objects in the situation under consideration really have wrong
> type?  The problem is that one table is not partition of another.
> However, it's possibly that they could be attached without changing of
> their types.  So, I think about
> ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE.  What do you think?
>

It's ok for me. Please check the v2 patch.

-- 
Thanks,
Tender Wang