1 files changed, 22 insertions, 0 deletions
diff --git a/db/migrate/20200702201039_change_prometheus_metrics_identifier_index.rb b/db/migrate/20200702201039_change_prometheus_metrics_identifier_index.rb
new file mode 100644
index 00000000000..248195c8c75
--- /dev/null
+++ b/db/migrate/20200702201039_change_prometheus_metrics_identifier_index.rb
@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+class ChangePrometheusMetricsIdentifierIndex < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  NEW_INDEX = :index_prometheus_metrics_on_identifier_and_null_project
+  OLD_INDEX = :index_prometheus_metrics_on_identifier
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index            :prometheus_metrics, :identifier, name: NEW_INDEX, unique: true, where: 'project_id IS NULL'
+    remove_concurrent_index_by_name :prometheus_metrics, OLD_INDEX
+  end
+
+  def down
+    add_concurrent_index            :prometheus_metrics, :identifier, name: OLD_INDEX, unique: true
+    remove_concurrent_index_by_name :prometheus_metrics, NEW_INDEX
+  end
+end