1 files changed, 23 insertions, 0 deletions
diff --git a/lib/arel/relations/projection.rb b/lib/arel/relations/projection.rb
new file mode 100644
index 0000000000..f09d4f894b
--- /dev/null
+++ b/lib/arel/relations/projection.rb
@@ -0,0 +1,23 @@
+module Arel
+  class Projection < Compound
+    attr_reader :projections
+    
+    def initialize(relation, *projections)
+      @relation, @projections = relation, projections
+    end
+
+    def attributes
+      projections.collect { |p| p.bind(self) }
+    end
+    
+    def ==(other)
+      self.class  == other.class    and
+      relation    == other.relation and
+      projections == other.projections
+    end
+    
+    def aggregation?
+      attributes.any?(&:aggregation?)
+    end
+  end
+end
+\ No newline at end of file