1 files changed, 27 insertions, 0 deletions
diff --git a/lib/gitlab/background_migration/backfill_project_namespace_details.rb b/lib/gitlab/background_migration/backfill_project_namespace_details.rb
new file mode 100644
index 00000000000..9bee3cf21e8
--- /dev/null
+++ b/lib/gitlab/background_migration/backfill_project_namespace_details.rb
@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+module Gitlab
+  module BackgroundMigration
+    # Backfill project namespace_details for a range of projects
+    class BackfillProjectNamespaceDetails < ::Gitlab::BackgroundMigration::BatchedMigrationJob
+      operation_name :backfill_project_namespace_details
+
+      def perform
+        each_sub_batch do |sub_batch|
+          upsert_project_namespace_details(sub_batch)
+        end
+      end
+
+      def upsert_project_namespace_details(relation)
+        connection.execute(
+          <<~SQL
+          INSERT INTO namespace_details (description, description_html, cached_markdown_version, created_at, updated_at, namespace_id)
+            SELECT projects.description, projects.description_html, projects.cached_markdown_version, now(), now(), projects.project_namespace_id
+            FROM projects
+            WHERE projects.id IN(#{relation.select(:id).to_sql})
+          ON CONFLICT (namespace_id) DO NOTHING;
+        SQL
+        )
+      end
+    end
+  end
+end