Robert Haas <robertmh...@gmail.com> writes: > I don't really understand how a version number helps. It's not like > there is going to be a v2 that is in all ways better than v1. If there > are different algorithms here, they are going to be customized for > different needs.
Yeah, I agree --- a version number is the wrong way to think about this. It's gonna be more like algorithm foo versus algorithm bar versus algorithm baz, where each one is better for a specific set of use-cases. Julien already noted the point about hashing object OIDs versus object names; one can easily imagine disagreeing with pg_stat_statement's choices about ignoring values of constants; other properties of statements might be irrelevant for some use-cases; and so on. I'm okay with moving pg_stat_statement's existing algorithm into core as long as there's a way for extensions to override it. With proper design, that would allow extensions that do override it to coexist with pg_stat_statements (thereby redefining the latter's idea of which statements are "the same"), which is something that doesn't really work nicely today. regards, tom lane