On Sun, Jul 26, 2020 at 1:27 PM Chris Travers <chris.trav...@adjust.com> wrote: > The first (probably the best) would be a solution along the lines of yours > along with a session-level GUC variable which could determine whether case > branches can fold constants.
Bluntly, that seems like a terrible idea. It's great if you are an expert DBA, because then you can adjust the behavior on your own system according to what works best for you. But if you are trying to write portable code that will work on any PostgreSQL instance, you now have to remember to test it with every possible value of the GUC and make sure it behaves the same way under all of them. That is a major burden on authors of tools and extensions, and if we add even three or four such GUCs with three or four possible values each, there are suddenly dozens or even hundreds of possible combinations to test. I think that adding GUCs for this kind of thing is a complete non-starter for that reason. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company
