Re: wrong relkind error messages

On Thu, Jun 24, 2021 at 10:12:49AM +0200, Peter Eisentraut wrote:
> There might be room for some wordsmithing in a few places, but generally I
> think this is complete.

I have been looking at that, and it seems to me that you nailed it.
That's a nice improvement compared to the existing error handling with
multiple relkinds.

+           ereport(ERROR,
+                   (errcode(ERRCODE_WRONG_OBJECT_TYPE),
+                    errmsg("ALTER action %s cannot be performed on relation \"%s\"",
+                           action_str, RelationGetRelationName(rel)),
+                    errdetail_relkind_not_supported(rel->rd_rel->relkind)));
Perhaps the result of alter_table_type_to_string() is worth a note for
translators?

+       case AT_DetachPartitionFinalize:
+           return "DETACH PARTITION FINALIZE";
To be exact, I think that this one should be "DETACH PARTITION
... FINALIZE".

+       if (relkind == RELKIND_INDEX || relkind == RELKIND_PARTITIONED_INDEX)
+           ereport(ERROR,
+                   (errcode(ERRCODE_WRONG_OBJECT_TYPE),
+                    errmsg("cannot change schema of index \"%s\"",
+                           rv->relname),
+                    errhint("Change the schema of the table instead.")));
+       else if (relkind == RELKIND_COMPOSITE_TYPE)
+           ereport(ERROR,
+                   (errcode(ERRCODE_WRONG_OBJECT_TYPE),
+                    errmsg("cannot change schema of composite type
\"%s\"",
+                           rv->relname),
+                    errhint("Use ALTER TYPE instead.")));
I would simplify this part by removing the errhint(), and use "cannot
change schema of relation .." as error string, with a dose of
errdetail_relkind_not_supported().

+                errmsg("relation \"%s\" cannot have triggers",
+                       RelationGetRelationName(rel)),
Better as "cannot create/rename/remove triggers on relation \"%s\""
for the three code paths of trigger.c?

+                errmsg("relation \"%s\" cannot have rules",
[...]
+                errmsg("relation \"%s\" cannot have rules",
For rewriteDefine.c, this could be "cannot create/rename rules on
relation".
--
Michael