Hi, Chao!

On Wed, May 20, 2026 at 2:37 AM Chao Li <[email protected]> wrote:
> > On May 19, 2026, at 19:00, Alexander Korotkov <[email protected]> wrote:
> > On Tue, May 19, 2026 at 5:50 AM Chao Li <[email protected]> wrote:
> >>> On May 18, 2026, at 20:04, Alexander Korotkov <[email protected]> 
> >>> wrote:
> >>>
> >>> On Mon, May 18, 2026 at 2:57 PM Chao Li <[email protected]> wrote:
> >>>>> <v3-0003-Clarify-SPLIT-PARTITION-bound-requirements-in-doc.patch><v3-0001-Fix-SPLIT-PARTITION-range-bound-validation-with-D.patch><v3-0002-Fix-SPLIT-PARTITION-hint-for-DEFAULT-partition-bo.patch><v3-0004-Reject-degenerate-SPLIT-PARTITION-with-DEFAULT-pa.patch>
> >>>>
> >>>> v3-0001 through v3-0003 look good to me.
> >>>>
> >>>> For v3-0004, I have a suspicion, but it's late here and my brain is 
> >>>> getting slow, so I would like to study it more tomorrow.
> >>>
> >>> Sure, take your time.
> >>>
> >>> ------
> >>> Regards,
> >>> Alexander Korotkov
> >>> Supabase
> >>
> >> My suspicion was that check_split_partition_not_same_bound() now has two 
> >> paths. The RANGE path honors collation, while the LIST path does not. So I 
> >> spent some time creating a test that uses a case-insensitive collation:
> >> ```
> >> evantest=# create collation case_insensitive (provider=icu, 
> >> locale='und-u-ks-level2', deterministic = false);
> >> CREATE COLLATION
> >> evantest=# create table t (b text collate case_insensitive) partition by 
> >> list (b);
> >> CREATE TABLE
> >> evantest=# create table tp_ab partition of t for values in ('a', 'b');
> >> CREATE TABLE
> >> evantest=# alter table t split partition tp_ab into
> >> evantest-#   (partition tp_a for values in ('a', 'A'),
> >> evantest(#   partition tp_default default);
> >> ERROR:  cannot split partition "tp_ab" only to add a DEFAULT partition
> >> LINE 2:   (partition tp_a for values in ('a', 'A'),
> >>                     ^
> >> DETAIL:  The non-DEFAULT partition would keep the same partition bound.
> >> HINT:  Use CREATE TABLE ... PARTITION OF ... DEFAULT to add a DEFAULT 
> >> partition.
> >> ```
> >>
> >> In this test, the split partition’s bound is ('a', 'b'), and the new 
> >> partition’s bound is ('a', 'A'). Their list lengths are both 2, but the 
> >> two bounds are actually different, because 'a' and 'A' are considered 
> >> equal by the collation.
> >>
> >> So, in the LIST path, since check_partition_bounds_for_split_list() has 
> >> already ensured that the new partition’s bound is contained within the 
> >> split partition’s bound, we need to check the reverse direction as well. 
> >> Whether the split partition’s bound is also contained in the new 
> >> partition’s bound. If yes, the two bounds are identical.
> >>
> >> See the attached v4 for my changes for 0004. 0001-0003 are unchanged. 
> >> Since 0001 and 0003 are independent of 0004, maybe they can be pushed 
> >> first.
> >
> > I've pushed 0001-0003.
>
> Thanks for pushing them.
>
> > Thank you for discovering the collation issue
> > in 0004.  Note that original approach of using
> > partition_bounds_equal() can't handle different collations too (as it
> > internally uses datumIsEqual()).
>
> Yes, I realized that while reviewing v3. That’s reason I didn’t get back v2 
> and only worked again based on v3.
>
> > I've revised the remaining patch:
> > made function header comment a bit more detailed
>
> This part looks good to me.
>
> > and added additional
> > regression tests.  Please, check.
> >
>
> But I don’t see any change for regression test between v4 and v5. Maybe you 
> forgot to save your changes?

Sorry, I just mess up, no changes in tests.
I'm going to push this if no objection.

------
Regards,
Alexander Korotkov
Supabase


Reply via email to