diff --git a/lib/ecto/adapters/postgres/connection.ex b/lib/ecto/adapters/postgres/connection.ex
index d8f063f7..7de5bb1f 100644
--- a/lib/ecto/adapters/postgres/connection.ex
+++ b/lib/ecto/adapters/postgres/connection.ex
@@ -28,6 +28,12 @@ if Code.ensure_loaded?(Postgrex) do
         ),
         do: [foreign_key: constraint]
 
+    def to_constraints(
+          %Postgrex.Error{postgres: %{code: :restrict_violation, constraint: constraint}},
+          _opts
+        ),
+        do: [foreign_key: constraint]
+
     def to_constraints(
           %Postgrex.Error{postgres: %{code: :exclusion_violation, constraint: constraint}},
           _opts