RE: Logical replication row filter loses unchanged toasted columns

Hi,

On Tuesday, August 25, 2026 6:16 PM Kuroda, Hayato <kuroda(dot)hayato(at)fujitsu(dot)com> wrote:
> > Here is the patch (on HEAD) for the suggested approach. I extended
> > extractReplicaIdentity to also extract unchanged toasted columns, as
> > it fits best there, we only need to log unchanged toast columns when
> > the replica identity changes.
>
> Thanks for posting the patch.
> I cannot find any the conceptual issues. I considered the alternative that new
> tuple can have un-changed toasted values, but it seems not good for the crash
> recovery: the code uses the tuple in the WAL as-is, so we should have the
> pointer to the toast table. Few small comments:
>
> ```
> +#include "catalog/pg_publication.h"
> ```
>
> I could compile the code without the inclusion, maybe because we use
> RelationHasPubRowFilterForUpdate() to obtain the rf_exists_for_update.
>
> ```
> + * to protect unchanged, non-replica-identity, TOASTed column
> + values that
> ```
>
> Not sure the term "protect" correct. How about "preserve"? Because we try
> to keep the toast value on the memory in heap_update().

Thanks for the comments. They look good to me and I have addressed them
in V4 patch.

Best Regards,
Zhijie Hou