default_scope adds order clause to aggregation queries about rails

[josevalim]

@jonleighton and @tenderlove, could you please check? ❤️

[jonleighton]

@rubymaverick: How does this code behave on 3-0-stable? (Assuming you define the default scope using the class-level macro, of course.) Thanks.

[ericallam]

@jonleighton in 3-0 stable the default scope is ignored, so the query above just becomes:

SELECT COUNT(*) FROM "users"

Also, FYI, if you do SELECT COUNT(*) FROM "users" ORDER BY created_at DESC in postgresql it will raise an error (sqlite just ignores it)

[jonleighton]

Okay, I will fix. We shouldn't just discard the default scope entirely though - if you have default_scope where(:published => true) or something then you would expect that to affect the count query.

[gnufied]

Won't just delegating aggregation queries to :unscoped solve the problem?