diff --git a/app/repositories/orient_db/learning_object/relation.rb b/app/repositories/orient_db/learning_object/relation.rb
index f56115f8376769293f9a8cda26c5d00be323b3f6..a80bb39718fdfd30c582c201c399ae7d2b423ad6 100644
--- a/app/repositories/orient_db/learning_object/relation.rb
+++ b/app/repositories/orient_db/learning_object/relation.rb
@@ -3,8 +3,9 @@ module OrientDb
     class Relation < OrientDb::Relation
       include OrientDb::Methods::EdgeMethods
 
-      def initialize(learning_object)
+      def initialize(learning_object, connection)
         @learning_object = learning_object
+        @connection = connection
       end
 
     end
diff --git a/app/repositories/orient_db/learning_object/relations_chain.rb b/app/repositories/orient_db/learning_object/relations_chain.rb
index c5aa198dd9c3e343ebbe31075416f26649282c02..6f6726b0f5a92a6cb1d9a8e731053a6c183865dd 100644
--- a/app/repositories/orient_db/learning_object/relations_chain.rb
+++ b/app/repositories/orient_db/learning_object/relations_chain.rb
@@ -4,9 +4,9 @@ module OrientDb
 
       def relations
         [
-            OrientDb::LearningObject::SubjectsRelations.new(object),
-            OrientDb::LearningObject::AttributesRelations.new(object),
-            OrientDb::LearningObject::PublisherRelation.new(object)
+            OrientDb::LearningObject::SubjectsRelations.new(object, connection),
+            OrientDb::LearningObject::AttributesRelations.new(object, connection),
+            OrientDb::LearningObject::PublisherRelation.new(object, connection)
         ]
       end
 
diff --git a/app/repositories/orient_db/relation.rb b/app/repositories/orient_db/relation.rb
index 2d2bbcbacdcd6a487b5ea171abf8600d9e7a1474..e13dc2fc98dfffa2f17cdfb7a1dec83d0489d92d 100644
--- a/app/repositories/orient_db/relation.rb
+++ b/app/repositories/orient_db/relation.rb
@@ -2,7 +2,7 @@ module OrientDb
 
   ##abstract class Relation
   class Relation
-    
+
     def can_create?
       raise NotImplementedError, 'Relation#can_execute? is an abstract method.'
     end
@@ -13,6 +13,8 @@ module OrientDb
 
     protected
 
+    attr_accessor :connection
+
     def execute
       raise NotImplementedError, 'Relation#execute is an abstract method.'
     end
diff --git a/app/repositories/orient_db/relation_chain.rb b/app/repositories/orient_db/relation_chain.rb
index 28f04db1064d9303eec7fa97d0311697a808ff68..fae4ba62d9f3ddab69297da180ec33a57f432f49 100644
--- a/app/repositories/orient_db/relation_chain.rb
+++ b/app/repositories/orient_db/relation_chain.rb
@@ -1,9 +1,10 @@
 module OrientDb
   class RelationChain
-    attr_reader :object
+    attr_reader :object, :connection
 
-    def initialize(object)
+    def initialize(object, connection)
       @object = object
+      @connection = connection
     end
 
     def create
diff --git a/app/repositories/orient_db/subject/relation.rb b/app/repositories/orient_db/subject/relation.rb
index df88a69c76714eadcaf609221966f0a6632e8758..9dad6a50f4cc3d4ce83c89fe7af49625f16329bb 100644
--- a/app/repositories/orient_db/subject/relation.rb
+++ b/app/repositories/orient_db/subject/relation.rb
@@ -3,8 +3,9 @@ module OrientDb
     class Relation < OrientDb::Relation
       include OrientDb::Methods::EdgeMethods
 
-      def initialize(subject)
+      def initialize(subject, connection)
         @subject = subject
+        @connection = connection
       end
 
     end
diff --git a/app/repositories/orient_db/subject/relations_chain.rb b/app/repositories/orient_db/subject/relations_chain.rb
index 3ef3ba941ec1076d717a2f86c0fa11c4525bcd32..fb26cf899a06b13294b55a37f9cf347943580e9e 100644
--- a/app/repositories/orient_db/subject/relations_chain.rb
+++ b/app/repositories/orient_db/subject/relations_chain.rb
@@ -4,8 +4,8 @@ module OrientDb
 
       def relations
         [
-            OrientDb::Subject::SubtopicsRelations.new(object),
-            OrientDb::Subject::SupertopicsRelations.new(object)
+            OrientDb::Subject::SubtopicsRelations.new(object, connection),
+            OrientDb::Subject::SupertopicsRelations.new(object, connection)
         ]
       end