Re: COPY (INSERT/UPDATE/DELETE .. RETURNING ..)

On 11/19/15 1:17 PM, Michael Paquier wrote:
> On Thu, Nov 19, 2015 at 11:04 AM, Marko Tiikkaja wrote:
>> Further, if someone's going to add new stuff to PreparableStmt, she should
>> probably think about whether it would make sense to add it to COPY and CTEs
>> from day one, too, and in that case not splitting them up is actually a win.
>
> Personally, I would take it on the safe side and actually update it.
> If someone were to add a new node type in PreparableStmt I am pretty
> sure that we are going to forget to update the COPY part, leading us
> to unwelcome bugs. And that would not be cool.

They'd have to get past this:
+       if (query->commandType != CMD_SELECT &&
+           query->returningList == NIL)
+       {
+           ereport(ERROR,
+                       (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+                        errmsg("COPY query must have a RETURNING 
clause")));
+       }

Of course, something might break if we added a new statement type which 
supported RETURNING, but I'm really not worried about that.  I'm not 
dead set against adding some Assert(IsA()) calls here, but I don't see 
the point.


.m