We moved more and more away from passing options to finder / calculation methods. The `:distinct` option in `#count` was one of the remaining places. Since we can now combine `Relation#distinct` with `Relation#count` the option is no longer necessary and can be deprecated.
The similarity of `Relation#uniq` to `Array#uniq` is confusing. Since our Relation API is close to SQL terms I renamed `#uniq` to `#distinct`. There is no deprecation. `#uniq` and `#uniq!` are aliases and will continue to work. I also updated the documentation to promote the use of `#distinct`.
…d' is the only pluck query that translates into the aforementioned SQL
…ted [ci skip]
…ation Fix build issue with postgresql.
Execute_grouped_calculation is one of those places where ActiveRecord forgets that it has ARel underpinnings, and assumes that the values provided to group_values are strings. This artificially hobbles otherwise functional code. This patch stops assuming that incoming values respond to to_sym, stops using string interpolation for table aliases on objects that support aliasing, and stops unnecessarily joining group_values on the relation. Additionally, it calls to_sql, if available, on objects sent to column_alias_for, in order to get a more reasonable alias string than a non-string's default to_str method.