1 files changed, 16 insertions, 0 deletions
diff --git a/lib/arel/relations/compound.rb b/lib/arel/relations/compound.rb
new file mode 100644
index 0000000000..4ffac6d1c3
--- /dev/null
+++ b/lib/arel/relations/compound.rb
@@ -0,0 +1,16 @@
+module Arel
+  class Compound < Relation
+    attr_reader :relation
+    
+    hash_on :relation
+    
+    delegate :joins, :selects, :orders, :groupings, :table_sql, :inserts, :taken,
+             :skipped, :name, :alias, :aggregation?, :alias?, :prefix_for, :column_for,
+             :engine,
+             :to => :relation
+    
+    def attributes
+      relation.attributes.collect { |a| a.bind(self) }
+    end
+  end
+end
+\ No newline at end of file