1 files changed, 48 insertions, 0 deletions
diff --git a/db/post_migrate/20210611080951_fix_missing_traversal_ids.rb b/db/post_migrate/20210611080951_fix_missing_traversal_ids.rb
new file mode 100644
index 00000000000..45728ef26f5
--- /dev/null
+++ b/db/post_migrate/20210611080951_fix_missing_traversal_ids.rb
@@ -0,0 +1,48 @@
+# frozen_string_literal: true
+
+class FixMissingTraversalIds < ActiveRecord::Migration[6.1]
+  include Gitlab::Database::MigrationHelpers
+
+  ROOTS_MIGRATION = 'BackfillNamespaceTraversalIdsRoots'
+  CHILDREN_MIGRATION = 'BackfillNamespaceTraversalIdsChildren'
+  DOWNTIME = false
+  BATCH_SIZE = 1_000
+  SUB_BATCH_SIZE = 50
+  DELAY_INTERVAL = 2.minutes
+  ROOT_NS_INDEX_NAME = 'tmp_index_namespaces_empty_traversal_ids_with_root_namespaces'
+  CHILD_INDEX_NAME = 'tmp_index_namespaces_empty_traversal_ids_with_child_namespaces'
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index :namespaces, :id, where: "parent_id IS NULL AND traversal_ids = '{}'", name: ROOT_NS_INDEX_NAME
+    add_concurrent_index :namespaces, :id, where: "parent_id IS NOT NULL AND traversal_ids = '{}'", name: CHILD_INDEX_NAME
+
+    # Personal namespaces and top-level groups
+    final_delay = queue_background_migration_jobs_by_range_at_intervals(
+      ::Gitlab::BackgroundMigration::BackfillNamespaceTraversalIdsRoots::Namespace.base_query.where("traversal_ids = '{}'"),
+       ROOTS_MIGRATION,
+       DELAY_INTERVAL,
+       batch_size: BATCH_SIZE,
+       other_job_arguments: [SUB_BATCH_SIZE],
+       track_jobs: true
+    )
+    final_delay += DELAY_INTERVAL
+
+    # Subgroups
+    queue_background_migration_jobs_by_range_at_intervals(
+      ::Gitlab::BackgroundMigration::BackfillNamespaceTraversalIdsChildren::Namespace.base_query.where("traversal_ids = '{}'"),
+       CHILDREN_MIGRATION,
+       DELAY_INTERVAL,
+       batch_size: BATCH_SIZE,
+       initial_delay: final_delay,
+       other_job_arguments: [SUB_BATCH_SIZE],
+       track_jobs: true
+    )
+  end
+
+  def down
+    remove_concurrent_index_by_name :namespaces, ROOT_NS_INDEX_NAME
+    remove_concurrent_index_by_name :namespaces, CHILD_INDEX_NAME
+  end
+end