> On Jan 28, 2026, at 10:49, Chao Li <[email protected]> wrote:
> 
> 
> 
>> On Jan 27, 2026, at 16:30, Chao Li <[email protected]> wrote:
>> 
>> 
>> 
>>> On Jan 27, 2026, at 15:59, Chao Li <[email protected]> wrote:
>>> 
>>> 
>>> 
>>>> On Jan 27, 2026, at 15:39, Michael Paquier <[email protected]> wrote:
>>>> 
>>>> On Tue, Jan 27, 2026 at 01:13:32PM +0800, Chao Li wrote:
>>>>> I found this bug while working on a related patch [1].
>>>>> 
>>>>> When ALTER TABLE ... ALTER COLUMN TYPE causes an index rebuild, and
>>>>> that index is used as REPLICA IDENTITY on a partitioned table, the
>>>>> replica identity marking on partitions can be silently lost after the
>>>>> rebuild.
>>>> 
>>>> I am slightly confused by the tests included in the proposed patch.
>>>> On HEAD, if I undo the proposed changes of tablecmds.c, the tests
>>>> pass.  If I run the tests of the patch with the changes of
>>>> tablecmds.c, the tests also pass.  
>>> 
>>> Oops, that isn’t supposed to be so. I’ll check the test.
>>> 
>> 
>> Okay, I see the problem is here:
>> ```
>> +CREATE UNIQUE INDEX test_replica_identity_partitioned_pkey ON 
>> test_replica_identity_partitioned (id);
>> ```
>> 
>> I missed to add column “val” into the index, so that alter type of val 
>> didn’t cause index rebuild.
>> 
>> Ideally, it’s better to also verify that index OIDs should have changed 
>> before and after alter column type, but I haven’t figured out how to do so. 
>> Do you have an idea?
> 
> I just updated the test to store index OIDs before and after rebuild into 2 
> temp tables, so that we can compare the OIDs to verify rebuild happens and 
> replica identity preserved.
> 
> I tried to port the test to master branch, and the test failed. From the test 
> diff file, we can see replica identity lost on 3 leaf partitions:
> ```
> @@ -360,9 +360,9 @@
>   ORDER BY b.index_name;
>                     index_name                     | rebuilt | ri_lost
> ---------------------------------------------------+---------+---------
> - test_replica_identity_partitioned_p1_id_val_idx   | t       | f
> - test_replica_identity_partitioned_p2_1_id_val_idx | t       | f
> - test_replica_identity_partitioned_p2_2_id_val_idx | t       | f
> + test_replica_identity_partitioned_p1_id_val_idx   | t       | t
> + test_replica_identity_partitioned_p2_1_id_val_idx | t       | t
> + test_replica_identity_partitioned_p2_2_id_val_idx | t       | t
>  test_replica_identity_partitioned_p2_id_val_idx   | t       | f
>  test_replica_identity_partitioned_pkey            | t       | f
> (5 rows)
> ```
> 
> With this patch, the test passes and all replica identity are preserved.
> 
> PFA v3:
> * Enhanced the test.
> * A small change in find_partition_replica_identity_indexes(): if we will not 
> update a partition, then unlock it.
> 
> Best regards,
> --
> Chao Li (Evan)
> HighGo Software Co., Ltd.
> https://www.highgo.com/
> 
> 
> 
> 
> <v3-0001-tablecmds-fix-bug-where-index-rebuild-loses-repli.patch>

The CF asked for a rebase, thus rebased as v4.

Best regards,
--
Chao Li (Evan)
HighGo Software Co., Ltd.
https://www.highgo.com/




Attachment: v4-0001-tablecmds-fix-bug-where-index-rebuild-loses-repli.patch
Description: Binary data

Reply via email to