Horton

Re: partitioning and identity column

Alexander Law <exclusion@gmail.com>

View thread View on postgr.es
From: Alexander Lakhin <exclusion@gmail.com>
To: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Cc: Peter Eisentraut <peter@eisentraut.org>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2024-04-26T18:00:01Z
Lists: pgsql-hackers 
26.04.2024 15:57, Ashutosh Bapat wrote:
> Thanks Alexander for the report.
>
> On Fri, Apr 26, 2024 at 5:30 PM Alexander Lakhin <exclusion@gmail.com> wrote:
>
>
>     CREATE TABLE tbl3 (LIKE tbl2 INCLUDING IDENTITY);
>     ERROR:  no owned sequence found
>
>
> I don't think creating a table like a partition is common or even useful. Usually it would create it from partitithe 
> oned table. But if we consider that to be a use case, I think the error is expected since a partition doesn't have its 
> own identity; it shares it with the partitioned table. Maybe we could give a better message. But I will look into this 
> and fix it if the solution makes sense.

Maybe it's uncommon, but it's allowed, so users may want to
CREATE TABLE sometable (LIKE partX INCLUDING ALL), for example, if the
partition has a somewhat different structure. And thinking about how such
a restriction could be described in the docs, I would prefer to avoid this
error at the implementation level.

>
> Do you want to track this in open items?
>

If you are inclined to fix this behavior,  I would add this item.

Best regards,
Alexander

Commits

  1. Fix assorted bugs related to identity column in partitioned tables

  2. Remove extra check_stack_depth() from dropconstraint_internal()

  3. Support identity columns in partitioned tables

  4. doc: Add Identity Column section under Data Definition chapter

  5. Assert that partition inherits from only one parent in MergeAttributes()

  6. doc: Decorate PostgreSQL with productname tag

  7. Fix prologue of get_partition_ancestors()