2 files changed, 18 insertions, 3 deletions
diff --git a/lib/arel/algebra/relations/operations/join.rb b/lib/arel/algebra/relations/operations/join.rb
index e47d9fa9e0..e9320f28e1 100644
--- a/lib/arel/algebra/relations/operations/join.rb
+++ b/lib/arel/algebra/relations/operations/join.rb
@@ -3,12 +3,19 @@ module Arel
     attributes :relation1, :relation2, :predicates
     deriving :==
     delegate :name, :to => :relation1
-    hash_on :relation1
 
     def initialize(relation1, relation2 = Nil.instance, *predicates)
       @relation1, @relation2, @predicates = relation1, relation2, predicates
     end
 
+    def hash
+      @hash ||= :relation1.hash
+    end
+
+    def eql?(other)
+      self == other
+    end
+
     def attributes
       @attributes ||= (relation1.externalize.attributes +
         relation2.externalize.attributes).collect { |a| a.bind(self) }
diff --git a/lib/arel/algebra/relations/utilities/compound.rb b/lib/arel/algebra/relations/utilities/compound.rb
index 676d80a737..5e775618f1 100644
--- a/lib/arel/algebra/relations/utilities/compound.rb
+++ b/lib/arel/algebra/relations/utilities/compound.rb
@@ -1,7 +1,6 @@
 module Arel
   class Compound < Relation
     attr_reader :relation
-    hash_on :relation
     delegate :joins, :join?, :inserts, :taken, :skipped, :name, :externalizable?,
              :column_for, :engine,
              :to => :relation
@@ -14,7 +13,16 @@ module Arel
       OPERATION
     end
 
-    private
+    def hash
+      @hash ||= :relation.hash
+    end
+
+    def eql?(other)
+      self == other
+    end
+
+  private
+
     def arguments_from_block(relation, &block)
       block_given?? [yield(relation)] : []
     end