Tom Lane wrote: > much anything that can generate a row. The patch as you have it > provides nothing more than syntactic sugar for something people can do > anyway. The reason people want this syntax is that they expect to be > able to write, say, > > UPDATE mytab SET (foo, bar, baz) = > (SELECT alpha, beta, gamma FROM othertab WHERE key = mytab.key); > > and with something like that you can't break apart the row-valued > expression in the grammar. So in reality the feature has to propagate > much further into the backend than this.
That UPDATE example is interesting because I remember when using Informix that I had to do a separate SELECT statement for each UPDATE column I wanted to update. I didn't realize that you could group columns and assign them from a single select --- clearly that is a powerful syntax we should support some day. -- Bruce Momjian [EMAIL PROTECTED] EnterpriseDB http://www.enterprisedb.com + If your life is a hard drive, Christ can be your backup. + ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
