Stephan Szabo <[EMAIL PROTECTED]> writes: > On Fri, 22 Aug 2008, Steve Johnson wrote: >> update certgroups >> set termgroupname = tg.termgroupname >> from certgroups c, termgroup tg >> where (c.days >= tg.mindays) and (c.days <= tg.maxdays);
> In recent PostgreSQL versions I believe this is properly written: > update certgroups c > set termgroupname = tg.termgroupname > from termgroup tg > where (c.days >= tg.mindays) and (c.days <= tg.maxdays); Yeah, in PG's eyes the former is creating a cartesian join between two versions of certgroups. I think MSSQL interprets the FROM reference as being the same as the update target, but we don't. > At least as of SQL2003, I think both of the above use extensions, Correct, the standard disallows a FROM clause altogether; and I'm not sure that they weren't right. No matter which way you resolve the above ambiguity, you've still got the problem that the update behavior is ill-defined if a given target row joins to more than one set of rows from the other table(s). regards, tom lane -- Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-sql