Hello 2008/5/3 Tom Lane <[EMAIL PROTECTED]>: > "Pavel Stehule" <[EMAIL PROTECTED]> writes: >> 2008/5/2 Heikki Linnakangas <[EMAIL PROTECTED]>: >>> How about taking a completely different strategy, and implement the >>> CASE-WHEN construct fully natively in plpgsql, instead of trying to convert >>> it to a single SQL CASE-WHEN expression? It's not a very good match anyway; > >> It was first variant. It's simpler for parsing and slower for >> execution :(. It means more than once expression evaluation and for >> simple case value casting and comparation. > > I agree with Heikki: this patch is seriously ugly, and "slower for > execution" isn't a good enough reason for saddling us with having > to maintain such a kluge in the parser. > > I don't really see why you should need to have multiple expression > evaluations, anyhow. Can't you evaluate the test expression once > and inject its value into the comparisons using CaseTestExpr, > the same way the core CASE-expression code works? > >
I have to look on this way. Regards Pavel Stehule regards, tom lane > -- Sent via pgsql-patches mailing list (pgsql-patches@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-patches