diff --git a/NzbDrone.Core/Datastore/MappingExtensions.cs b/NzbDrone.Core/Datastore/MappingExtensions.cs
new file mode 100644
index 000000000..bb5cfb3e8
--- /dev/null
+++ b/NzbDrone.Core/Datastore/MappingExtensions.cs
@@ -0,0 +1,49 @@
+using System;
+using System.Linq;
+using System.Reflection;
+using Marr.Data.Mapping;
+
+namespace NzbDrone.Core.Datastore
+{
+    public static class MappingExtensions
+    {
+        public static ColumnMapBuilder<T> RegisterModel<T>(this FluentMappings.MappingsFluentEntity<T> mapBuilder, string tableName) where T : ModelBase
+        {
+            return mapBuilder.Table.MapTable(tableName)
+                             .Columns
+                             .AutoMapPropertiesWhere(IsMappableProperty)
+                             .For(c => c.Id)
+                             .SetPrimaryKey()
+                             .SetReturnValue()
+                             .SetAutoIncrement();
+        }
+
+        public static bool IsMappableProperty(MemberInfo memberInfo)
+        {
+            var propertyInfo = memberInfo as PropertyInfo;
+
+            if (propertyInfo == null) return false;
+
+            if (propertyInfo.PropertyType.GetInterfaces().Any(i => i == typeof(IEmbeddedDocument)))
+            {
+                return true;
+            }
+
+            return propertyInfo.CanRead && propertyInfo.CanWrite && IsSimpleType(propertyInfo.PropertyType);
+        }
+
+        public static bool IsSimpleType(Type type)
+        {
+            if (type.IsGenericType && type.GetGenericTypeDefinition() == typeof(Nullable<>))
+            {
+                type = type.GetGenericArguments()[0];
+            }
+
+            return type.IsPrimitive
+                   || type.IsEnum
+                   || type == typeof(string)
+                   || type == typeof(DateTime)
+                   || type == typeof(Decimal);
+        }
+    }
+}
\ No newline at end of file
diff --git a/NzbDrone.Core/Datastore/RelationshipExtensions.cs b/NzbDrone.Core/Datastore/RelationshipExtensions.cs
new file mode 100644
index 000000000..e5338c836
--- /dev/null
+++ b/NzbDrone.Core/Datastore/RelationshipExtensions.cs
@@ -0,0 +1,33 @@
+using System;
+using System.Linq;
+using System.Linq.Expressions;
+using Marr.Data;
+using Marr.Data.Mapping;
+
+namespace NzbDrone.Core.Datastore
+{
+    public static class RelationshipExtensions
+    {
+        public static RelationshipBuilder<TParent> HasOne<TParent, TChild>(this ColumnMapBuilder<TParent> columnMapBuilder, Expression<Func<TParent, object>> portalExpression, Func<TParent, int> childIdSelector)
+            where TParent : ModelBase
+            where TChild : ModelBase
+        {
+            return columnMapBuilder.Relationships.AutoMapComplexTypeProperties<ILazyLoaded>()
+                                   .For(portalExpression)
+                                   .LazyLoad((db, parent) => db.Query<TChild>().Single(c => c.Id == childIdSelector(parent)));
+
+
+        }
+
+        public static RelationshipBuilder<TParent> HasMany<TParent, TChild>(this ColumnMapBuilder<TParent> columnMapBuilder, Expression<Func<TParent, object>> portalExpression, Func<TParent, int> childIdSelector)
+            where TParent : ModelBase
+            where TChild : ModelBase
+        {
+            return columnMapBuilder.Relationships.AutoMapComplexTypeProperties<ILazyLoaded>()
+                                   .For(portalExpression)
+                                   .LazyLoad((db, parent) => db.Query<TChild>().Where(c => c.Id == childIdSelector(parent)).ToList());
+
+
+        }
+    }
+}
\ No newline at end of file
diff --git a/NzbDrone.Core/Datastore/TableMapping.cs b/NzbDrone.Core/Datastore/TableMapping.cs
index 489a73ba2..e06bc8bd4 100644
--- a/NzbDrone.Core/Datastore/TableMapping.cs
+++ b/NzbDrone.Core/Datastore/TableMapping.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Linq.Expressions;
 using System.Reflection;
 using Marr.Data;
 using Marr.Data.Mapping;
@@ -38,9 +39,7 @@ public static void Map()
             Mapper.Entity<SceneMapping>().RegisterModel("SceneMappings");
 
             Mapper.Entity<History.History>().RegisterModel("History")
-                .Relationships.AutoMapComplexTypeProperties<ILazyLoaded>()
-                .For(c => c.Episode)
-                .LazyLoad((db, history) => db.Query<Episode>().Single(ep => ep.Id == history.EpisodeId));
+                .HasOne<History.History, Episode>(h => h.Episode, h => h.EpisodeId);
 
             Mapper.Entity<Series>().RegisterModel("Series")
                   .Relationships.AutoMapComplexTypeProperties<ILazyLoaded>()
@@ -60,6 +59,7 @@ public static void Map()
 
         }
 
+
         private static void RegisterMappers()
         {
             MapRepository.Instance.RegisterTypeConverter(typeof(Int32), new Int32Converter());
@@ -67,45 +67,5 @@ private static void RegisterMappers()
             MapRepository.Instance.RegisterTypeConverter(typeof(Enum), new EnumIntConverter());
             MapRepository.Instance.RegisterTypeConverter(typeof(QualityModel), new EmbeddedDocumentConverter());
         }
-
-
-        private static ColumnMapBuilder<T> RegisterModel<T>(this FluentMappings.MappingsFluentEntity<T> mapBuilder, string tableName) where T : ModelBase
-        {
-            return mapBuilder.Table.MapTable(tableName)
-                         .Columns
-                         .AutoMapPropertiesWhere(IsMappableProperty)
-                         .For(c => c.Id)
-                         .SetPrimaryKey()
-                         .SetReturnValue()
-                         .SetAutoIncrement();
-        }
-
-        private static bool IsMappableProperty(MemberInfo memberInfo)
-        {
-            var propertyInfo = memberInfo as PropertyInfo;
-
-            if (propertyInfo == null) return false;
-
-            if (propertyInfo.PropertyType.GetInterfaces().Any(i => i == typeof(IEmbeddedDocument)))
-            {
-                return true;
-            }
-
-            return propertyInfo.CanRead && propertyInfo.CanWrite && IsSimpleType(propertyInfo.PropertyType);
-        }
-
-        private static bool IsSimpleType(Type type)
-        {
-            if (type.IsGenericType && type.GetGenericTypeDefinition() == typeof(Nullable<>))
-            {
-                type = type.GetGenericArguments()[0];
-            }
-
-            return type.IsPrimitive
-                || type.IsEnum
-                || type == typeof(string)
-                || type == typeof(DateTime)
-                || type == typeof(Decimal);
-        }
     }
 }
\ No newline at end of file
diff --git a/NzbDrone.Core/NzbDrone.Core.csproj b/NzbDrone.Core/NzbDrone.Core.csproj
index 21292072c..89e6a0ddc 100644
--- a/NzbDrone.Core/NzbDrone.Core.csproj
+++ b/NzbDrone.Core/NzbDrone.Core.csproj
@@ -203,6 +203,7 @@
     <Compile Include="Datastore\EnumIntConverter.cs" />
     <Compile Include="Datastore\IEmbeddedDocument.cs" />
     <Compile Include="Datastore\LazyList.cs" />
+    <Compile Include="Datastore\MappingExtensions.cs" />
     <Compile Include="Datastore\Migration\Framework\MigrationController.cs" />
     <Compile Include="Datastore\Migration\Framework\MigrationOptions.cs" />
     <Compile Include="Datastore\Migration\Framework\NlogAnnouncer.cs" />
@@ -211,6 +212,7 @@
     <Compile Include="Datastore\MigrationType.cs" />
     <Compile Include="Datastore\ModelBase.cs" />
     <Compile Include="Datastore\BasicRepository.cs" />
+    <Compile Include="Datastore\RelationshipExtensions.cs" />
     <Compile Include="Datastore\TableMapping.cs" />
     <Compile Include="DecisionEngine\DownloadDecision.cs" />
     <Compile Include="DecisionEngine\IFetchableSpecification.cs" />