1 files changed, 19 insertions, 0 deletions
diff --git a/db/migrate/20220107091629_add_route_namespace_index.rb b/db/migrate/20220107091629_add_route_namespace_index.rb
new file mode 100644
index 00000000000..bc1044a24da
--- /dev/null
+++ b/db/migrate/20220107091629_add_route_namespace_index.rb
@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+class AddRouteNamespaceIndex < Gitlab::Database::Migration[1.0]
+  disable_ddl_transaction!
+  INDEX_NAME = 'index_routes_on_namespace_id'
+
+  def up
+    add_concurrent_index :routes, :namespace_id, unique: true, name: INDEX_NAME
+    add_concurrent_foreign_key :routes, :namespaces, column: :namespace_id, on_delete: :nullify, reverse_lock_order: true
+  end
+
+  def down
+    with_lock_retries do
+      remove_foreign_key_if_exists :routes, column: :namespace_id
+    end
+
+    remove_concurrent_index_by_name :routes, INDEX_NAME
+  end
+end