Swap FK ci_triggers to users for LFK

Removes FK for ci_triggers to users

Changelog: changed

db/post_migrate/20220119144458_remove_users_ci_triggers_owner_id_fk.rb

+# frozen_string_literal: true
+
+class RemoveUsersCiTriggersOwnerIdFk < Gitlab::Database::Migration[1.0]
+  disable_ddl_transaction!
+
+  def up
+    with_lock_retries do
+      execute('LOCK users, ci_triggers IN ACCESS EXCLUSIVE MODE')
+
+      remove_foreign_key_if_exists(:ci_triggers, :users, name: "fk_e8e10d1964")
+    end
+  end
+
+  def down
+    add_concurrent_foreign_key(:ci_triggers, :users, name: "fk_e8e10d1964", column: :owner_id, target_column: :id, on_delete: :cascade)
+  end
+end

db/schema_migrations/20220119144458

+85227d2aa0e984f12362484b23554a4feb1304d055d54da40e20812f2d8c5b9e
\ No newline at end of file

db/structure.sql

@@ -29930,9 +29930,6 @@ ALTER TABLE ONLY application_settings
 ALTER TABLE ONLY vulnerability_statistics
     ADD CONSTRAINT fk_e8b13c928f FOREIGN KEY (latest_pipeline_id) REFERENCES ci_pipelines(id) ON DELETE SET NULL;
 
-ALTER TABLE ONLY ci_triggers
-    ADD CONSTRAINT fk_e8e10d1964 FOREIGN KEY (owner_id) REFERENCES users(id) ON DELETE CASCADE;
-
 ALTER TABLE ONLY integrations
     ADD CONSTRAINT fk_e8fe908a34 FOREIGN KEY (group_id) REFERENCES namespaces(id) ON DELETE CASCADE;
 

lib/gitlab/database/gitlab_loose_foreign_keys.yml

@@ -162,3 +162,7 @@ ci_sources_pipelines:
   - table: projects
     column: source_project_id
     on_delete: async_delete
+ci_triggers:
+  - table: users
+    column: owner_id
+    on_delete: async_delete

spec/lib/gitlab/database/no_cross_db_foreign_keys_spec.rb

@@ -38,7 +38,6 @@ RSpec.describe 'cross-database foreign keys' do
       ci_stages.project_id
       ci_subscriptions_projects.downstream_project_id
       ci_subscriptions_projects.upstream_project_id
-      ci_triggers.owner_id
       ci_triggers.project_id
       ci_unit_tests.project_id
       ci_variables.project_id

spec/models/ci/trigger_spec.rb

@@ -61,4 +61,11 @@ RSpec.describe Ci::Trigger do
   it_behaves_like 'includes Limitable concern' do
     subject { build(:ci_trigger, owner: project.owner, project: project) }
   end
+
+  context 'loose foreign key on ci_triggers.owner_id' do
+    it_behaves_like 'cleanup by a loose foreign key' do
+      let!(:parent) { create(:user) }
+      let!(:model) { create(:ci_trigger, owner: parent) }
+    end
+  end
 end