1 files changed, 37 insertions, 0 deletions
diff --git a/db/migrate/20211011141242_create_namespaces_sync_trigger.rb b/db/migrate/20211011141242_create_namespaces_sync_trigger.rb
new file mode 100644
index 00000000000..91f64709f28
--- /dev/null
+++ b/db/migrate/20211011141242_create_namespaces_sync_trigger.rb
@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+class CreateNamespacesSyncTrigger < Gitlab::Database::Migration[1.0]
+  include Gitlab::Database::SchemaHelpers
+
+  enable_lock_retries!
+
+  TABLE_NAME = 'namespaces'
+  EVENT_TABLE_NAME = 'namespaces_sync_events'
+  FUNCTION_NAME = 'insert_namespaces_sync_event'
+  TRIGGER_ON_INSERT = 'trigger_namespaces_parent_id_on_insert'
+  TRIGGER_ON_UPDATE = 'trigger_namespaces_parent_id_on_update'
+
+  def up
+    create_trigger_function(FUNCTION_NAME) do
+      <<~SQL
+        INSERT INTO #{EVENT_TABLE_NAME} (namespace_id)
+        VALUES(COALESCE(NEW.id, OLD.id));
+        RETURN NULL;
+      SQL
+    end
+
+    create_trigger(TABLE_NAME, TRIGGER_ON_INSERT, FUNCTION_NAME, fires: 'AFTER INSERT')
+
+    create_trigger(TABLE_NAME, TRIGGER_ON_UPDATE, FUNCTION_NAME, fires: 'AFTER UPDATE') do
+      <<~SQL
+        WHEN (OLD.parent_id IS DISTINCT FROM NEW.parent_id)
+      SQL
+    end
+  end
+
+  def down
+    drop_trigger(TABLE_NAME, TRIGGER_ON_INSERT)
+    drop_trigger(TABLE_NAME, TRIGGER_ON_UPDATE)
+    drop_function(FUNCTION_NAME)
+  end
+end