Reorder source_project_id foreign key constraint

changelogs/unreleased/fix-project-deletion-timeout.yml

+---
+title: Reorder source_project_id foreign key constraint in merge_requests table
+merge_request: 60313
+author:
+type: changed

db/migrate/20210423171304_re_order_fk_source_project_id_in_merge_requests.rb

+# frozen_string_literal: true
+
+class ReOrderFkSourceProjectIdInMergeRequests < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  OLD_SOURCE_PROJECT_FK = 'fk_3308fe130c'
+  NEW_SOURCE_PROJECT_FK = 'fk_source_project'
+
+  def up
+    add_concurrent_foreign_key :merge_requests, :projects, column: :source_project_id, on_delete: :nullify, name: NEW_SOURCE_PROJECT_FK
+
+    remove_foreign_key_if_exists :merge_requests, column: :source_project_id, name: OLD_SOURCE_PROJECT_FK
+  end
+
+  def down
+    add_concurrent_foreign_key :merge_requests, :projects, column: :source_project_id, on_delete: :nullify
+
+    remove_foreign_key_if_exists :merge_requests, column: :source_project_id, name: NEW_SOURCE_PROJECT_FK
+  end
+end

db/schema_migrations/20210423171304

+06ead319cbc56b25769ed06b6a246d705b467d34a5d09ab9282e2d83c55511ba
\ No newline at end of file

db/structure.sql

@@ -25068,9 +25068,6 @@ ALTER TABLE ONLY approvals
 ALTER TABLE ONLY namespaces
     ADD CONSTRAINT fk_319256d87a FOREIGN KEY (file_template_project_id) REFERENCES projects(id) ON DELETE SET NULL;
 
-ALTER TABLE ONLY merge_requests
-    ADD CONSTRAINT fk_3308fe130c FOREIGN KEY (source_project_id) REFERENCES projects(id) ON DELETE SET NULL;
-
 ALTER TABLE ONLY ci_group_variables
     ADD CONSTRAINT fk_33ae4d58d8 FOREIGN KEY (group_id) REFERENCES namespaces(id) ON DELETE CASCADE;
 
@@ -27159,6 +27156,9 @@ ALTER TABLE ONLY ci_builds_metadata
 ALTER TABLE ONLY services
     ADD CONSTRAINT fk_services_inherit_from_id FOREIGN KEY (inherit_from_id) REFERENCES services(id) ON DELETE CASCADE;
 
+ALTER TABLE ONLY merge_requests
+    ADD CONSTRAINT fk_source_project FOREIGN KEY (source_project_id) REFERENCES projects(id) ON DELETE SET NULL;
+
 ALTER TABLE ONLY timelogs
     ADD CONSTRAINT fk_timelogs_issues_issue_id FOREIGN KEY (issue_id) REFERENCES issues(id) ON DELETE CASCADE;