diff --git a/relational-join/src/Database/Relational/Query/Internal/Context.hs b/relational-join/src/Database/Relational/Query/Internal/Context.hs
index d6635e7f..380e7357 100644
--- a/relational-join/src/Database/Relational/Query/Internal/Context.hs
+++ b/relational-join/src/Database/Relational/Query/Internal/Context.hs
@@ -7,7 +7,7 @@ module Database.Relational.Query.Internal.Context (
   nextAlias,
 
   updateProduct, takeProduct, restoreLeft,
-  updateRestriction,
+  addRestriction,
   updateOrderBy, takeOrderBys, restoreLowOrderBys,
 
   composeSQL
@@ -64,8 +64,8 @@ takeProduct ctx = (product ctx, updateProduct' (const Nothing) ctx)
 restoreLeft :: QueryProductNode -> Product.NodeAttr -> Context -> Context
 restoreLeft pL naR ctx = updateProduct (Product.growLeft pL naR) ctx
 
-updateRestriction :: Expr Bool -> Context -> Context
-updateRestriction e1 ctx =
+addRestriction :: Expr Bool -> Context -> Context
+addRestriction e1 ctx =
   ctx { restriction = Just . uf . restriction $ ctx }
   where uf  Nothing = e1
         uf (Just e0) = e0 `Projectable.and` e1
diff --git a/relational-join/src/Database/Relational/Query/Join.hs b/relational-join/src/Database/Relational/Query/Join.hs
index 182311c8..a8f13320 100644
--- a/relational-join/src/Database/Relational/Query/Join.hs
+++ b/relational-join/src/Database/Relational/Query/Join.hs
@@ -66,11 +66,11 @@ updateContext uf =
 
 updateJoinRestriction :: Expr Bool -> QueryJoin ()
 updateJoinRestriction e = updateContext (updateProduct d)  where
-  d  Nothing  = error "addProductRestriction: product is empty!"
+  d  Nothing  = error "on: product is empty!"
   d (Just pt) = restrictProduct pt e
 
 updateRestriction :: Expr Bool -> QueryJoin ()
-updateRestriction e = updateContext (Context.updateRestriction e)
+updateRestriction e = updateContext (Context.addRestriction e)
 
 takeProduct :: QueryJoin (Maybe QueryProductNode)
 takeProduct =  QueryJoin Context.takeProduct