diff options
Diffstat (limited to 'db/migrate/20171114162227_merge_requests_milestone_id_foreign_key.rb')
-rw-r--r-- | db/migrate/20171114162227_merge_requests_milestone_id_foreign_key.rb | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/db/migrate/20171114162227_merge_requests_milestone_id_foreign_key.rb b/db/migrate/20171114162227_merge_requests_milestone_id_foreign_key.rb new file mode 100644 index 00000000000..c005cf7d173 --- /dev/null +++ b/db/migrate/20171114162227_merge_requests_milestone_id_foreign_key.rb @@ -0,0 +1,39 @@ +# See http://doc.gitlab.com/ce/development/migration_style_guide.html +# for more information on how to write migrations for GitLab. + +class MergeRequestsMilestoneIdForeignKey < ActiveRecord::Migration + include Gitlab::Database::MigrationHelpers + + # Set this constant to true if this migration requires downtime. + DOWNTIME = false + + disable_ddl_transaction! + + class MergeRequest < ActiveRecord::Base + include EachBatch + + self.table_name = 'merge_requests' + + def self.with_orphaned_milestones + where('NOT EXISTS (SELECT true FROM milestones WHERE merge_requests.milestone_id = milestones.id)') + .where('milestone_id IS NOT NULL') + end + end + + def up + MergeRequest.with_orphaned_milestones.each_batch(of: 100) do |batch| + batch.update_all(milestone_id: nil) + end + + add_concurrent_foreign_key( + :merge_requests, + :milestones, + column: :milestone_id, + on_delete: :nullify + ) + end + + def down + remove_foreign_key_without_error(:merge_requests, column: :milestone_id) + end +end |