1 files changed, 19 insertions, 0 deletions
diff --git a/lib/arel/relations/grouping.rb b/lib/arel/relations/grouping.rb
new file mode 100644
index 0000000000..ccca600360
--- /dev/null
+++ b/lib/arel/relations/grouping.rb
@@ -0,0 +1,19 @@
+module Arel
+  class Grouping < Compound
+    attr_reader :expressions, :groupings
+
+    def initialize(relation, *groupings)
+      @relation, @groupings = relation, groupings.collect { |g| g.bind(relation) }
+    end
+
+    def ==(other)
+      self.class  == other.class      and
+      relation    == other.relation   and
+      groupings   == other.groupings
+    end
+
+    def aggregation?
+      true
+    end
+  end
+end
+\ No newline at end of file