Re: Parallel INSERT SELECT take 2

On Tue, May 11, 2021 at 10:41 PM houzj(dot)fnst(at)fujitsu(dot)com
<houzj(dot)fnst(at)fujitsu(dot)com> wrote:
>
> Attaching new version patches with the following changes:
>
> 0001
> Add a new function pg_get_max_parallel_hazard('table_name') returns char('s', 'u', 'r')
> which indicate whether it is safe, unsafe, or restricted to perform a DML.
>

Currently the 1st patch actually also contains the changes for the
Parallel-SELECT-for-INSERT functionality. This is not obvious.
So I think this should be split out into a separate patch (i.e. the
minor planner update and related planner comment changes,
is_parallel_allowed_for_modify() function, max_parallel_hazard()
update, XID changes).
Also, the regression tests' "serial_schedule" file has been removed
since you posted the v3-POC patches, so you need to remove updates for
that from your 3rd patch.

How about reorganisation of the patches like the following?

0001: CREATE ALTER TABLE PARALLEL DML
0002: parallel-SELECT-for-INSERT (planner changes,
max_parallel_hazard() update, XID changes)
0003: pg_get_parallel_safety()
0004: regression test updates

Regards,
Greg Nancarrow
Fujitsu Australia