grouping_array_or_grouping_element

# File activerecord/lib/arel/visitors/postgresql.rb, line 99
        def grouping_array_or_grouping_element(o, collector)
          if o.expr.is_a? Array
            collector << "( "
            visit o.expr, collector
            collector << " )"
          else
            visit o.expr, collector
          end
        end