Re: [PATCH] Rebuild CHECK constraints after generated column SET EXPRESSION

On Fri, May 15, 2026 at 1:06 AM Ayush Tiwari
<ayushtiwari(dot)slg01(at)gmail(dot)com> wrote:
>
> I've two minor follow-up comments/questions:
>
> 1. The "-- indedx with whole-row reference need rebuild" comment is
> still in the new SQL/expected blocks for both generated_stored and
> generated_virtual:
> "-- index with whole-row reference needs rebuild"
>
Thanks for finding the typo!

I did another round of code cleanup and cosmetic refactoring. Main
idea still the same: loop through
pg_constraint, pg_index, and pg_policy to locate all objects
containing whole-row
references, then error reporting or remember them for recreation.

The commit message was also updated.
Later, I will add this thread to
https://wiki.postgresql.org/wiki/PostgreSQL_19_Open_Items

> 2. The new policy error message:
>
> errmsg("ALTER TABLE / SET EXPRESSION is not supported for
> generated columns in tables that are part of a policy
> definition"),
> errdetail("%s contains whole row references.", ...)
>
> I still find this wording a bit awkward. Quoting "ALTER TABLE /
> SET EXPRESSION" as a syntactic form in the message is unusual for
> tablecmds.c, and the sentence is long. Could we keep it closer to
> the surrounding style.
>

+ if (subtype == AT_SetExpression)
+ ereport(ERROR,
+ errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("cannot alter generation
expression of table %s because %s uses its row type",
+ RelationGetRelationName(rel),
+ getObjectDescription(&pol_obj, false)),
+ errdetail("You might need to drop %s
first.", getObjectDescription(&pol_obj, false)));
What do you think?

--
jian
https://www.enterprisedb.com/