1 files changed, 30 insertions, 0 deletions
diff --git a/db/post_migrate/20210330091751_remove_records_without_group_from_webhooks_table.rb b/db/post_migrate/20210330091751_remove_records_without_group_from_webhooks_table.rb
new file mode 100644
index 00000000000..c384aa25ac4
--- /dev/null
+++ b/db/post_migrate/20210330091751_remove_records_without_group_from_webhooks_table.rb
@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+class RemoveRecordsWithoutGroupFromWebhooksTable < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  class WebHook < ActiveRecord::Base
+    include EachBatch
+
+    self.table_name = 'web_hooks'
+  end
+
+  class Group < ActiveRecord::Base
+    self.inheritance_column = :_type_disabled
+    self.table_name = 'namespaces'
+  end
+
+  def up
+    subquery = Group.select(1).where(Group.arel_table[:id].eq(WebHook.arel_table[:group_id]))
+
+    WebHook.each_batch(of: 500, column: :id) do |relation|
+      relation.where(type: 'GroupHook').where.not('EXISTS (?)', subquery).delete_all
+    end
+  end
+
+  def down
+    # no-op
+  end
+end