Grouping ands and ors in AREL
You can generate parentheses using Arel::Nodes::Grouping.
participants = Arel::Table.new("participants")arel = participants.grouping( participants[:accepted].eq(false).and(participants[:contact_id].eq(1))).or(participants[:id].eq(nil))arel.to_sql # => (("participants"."accepted" = 'f' AND "participants"."contact_id" = 1) OR "participants"."id" IS NULL)
I believe that according to the operator precedence
The problems is that AND has higher precedence than OR. So 1 AND 2 OR 3 is equivalent to (1 AND 2) OR 3. As a side note: if you use a wrapper like this one, you can write better looking code with Arel:
User.where((User[:created_at] > 3.days.ago) & (User[:enabled] == true))