Re: SQL-Invoked Procedures for 8.1

Oliver Jowett <oliver@opencloud.com> writes:
> The JDBC driver currently sends Describe/Execute and expects exactly one 
> of RowDescription/NoData followed by zero or more DataRows followed by 
> one of CommandComplete/EmptyQueryResponse/PortalSuspended. This seems 
> wrong if there could be multiple resultsets from a single Execute.

This is okay if you know the query was a SELECT, since we don't allow
ON SELECT rules that aren't view-like (ie, DO INSTEAD SELECT something-else).
Non-SELECT queries can return multiple result sets, though, as I
illustrated.  It's probably reasonable for the driver to throw these
away if it's not looking for a resultset at all.  Or you could follow
PQexec's lead and discard all but the last.

> How can clients distinguish multiple resultsets if they're using the 
> extended query protocol?

You'll get multiple repetitions of RowDescription/DataRows.
        regards, tom lane