Re: ALTER COLLATION misses errcode

On 30/10/2026 20:38, Kirill Reshke wrote:
> User running ALTER COLLATION receives an internal error:
>
> ALTER COLLATION "default" REFRESH VERSION;
> ERROR: cannot refresh version of default collation
> HINT: Use ALTER DATABASE ... REFRESH COLLATION VERSION instead.
>
> We do monitor our logs for XX00* error codes to check for data
> corruptions etc, so sql-reachable XX000 gives us a red alert.
>
> This simple one-liner should do:
>
> diff --git a/src/backend/commands/collationcmds.c
> b/src/backend/commands/collationcmds.c
> index cfa0e4610d9..1f6156f379b 100644
> --- a/src/backend/commands/collationcmds.c
> +++ b/src/backend/commands/collationcmds.c
> @@ -443,7 +443,8 @@ AlterCollation(AlterCollationStmt *stmt)
>
> if (collOid == DEFAULT_COLLATION_OID)
> ereport(ERROR,
> - (errmsg("cannot refresh version of default collation"),
> + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
> + errmsg("cannot refresh version of default collation"),
> /* translator: %s is an SQL command */
> errhint("Use %s instead.",
> "ALTER DATABASE ... REFRESH COLLATION VERSION")));

Is ERRCODE_FEATURE_NOT_SUPPORTED correct here? Is this something that we
just don't currently support, but we potentially could, or is it
something that just doesn't make sense?

- Heikki