Re: Allow batched insert during cross-partition updates

Hi Georgios,

On Wed, Mar 10, 2021 at 9:30 PM Georgios <gkokolatos@protonmail.com> wrote:
> I continued looking a bit at the patch, yet I am either failing to see fix or I am
> looking at the wrong thing. Please find attached a small repro of what my expectetions
> were.
>
> As you can see in the repro, I would expect the
>  UPDATE local_root_remote_partitions SET a = 2;
> to move the tuples to remote_partition_2 on the same transaction.
> However this is not the case, with or without the patch.
>
> Is my expectation of this patch wrong?

I think yes.  We currently don't have the feature you are looking for
-- moving tuples from one remote partition to another remote
partition.  This patch is not for adding that feature.

What we do support however is moving rows from a local partition to a
remote partition and that involves performing an INSERT on the latter.
This patch is for teaching those INSERTs to use batched mode if
allowed, which is currently prohibited.  So with this patch, if an
UPDATE moves 10 rows from a local partition to a remote partition,
then they will be inserted with a single INSERT command containing all
10 rows, instead of 10 separate INSERT commands.

--
Amit Langote
EDB: http://www.enterprisedb.com