1 files changed, 21 insertions, 0 deletions
diff --git a/db/post_migrate/20200305082858_add_uniqueness_index_to_label_title_and_project.rb b/db/post_migrate/20200305082858_add_uniqueness_index_to_label_title_and_project.rb
new file mode 100644
index 00000000000..ce235ba4aea
--- /dev/null
+++ b/db/post_migrate/20200305082858_add_uniqueness_index_to_label_title_and_project.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+class AddUniquenessIndexToLabelTitleAndProject < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  PROJECT_AND_TITLE = [:project_id, :title]
+
+  def up
+    add_concurrent_index :labels, PROJECT_AND_TITLE, where: "labels.group_id IS NULL", unique: true, name: "index_labels_on_project_id_and_title_unique"
+    remove_concurrent_index :labels, PROJECT_AND_TITLE, name: "index_labels_on_project_id_and_title"
+  end
+
+  def down
+    add_concurrent_index :labels, PROJECT_AND_TITLE, where: "labels.group_id IS NULL", unique: false, name: "index_labels_on_project_id_and_title"
+    remove_concurrent_index :labels, PROJECT_AND_TITLE, name: "index_labels_on_project_id_and_title_unique"
+  end
+end