Remove Temporary Index on Issues

changelogs/unreleased/321745-remove-temporary-index-idx_on_issues_where_service_desk_reply_to_i.yml

+---
+title: Remove temporary index on issues
+merge_request: 54387
+author: Lee Tickett @leetickett
+type: other

db/migrate/20210216223335_remove_index_on_issues_where_service_desk_reply_to_is_not_null.rb

+# frozen_string_literal: true
+
+class RemoveIndexOnIssuesWhereServiceDeskReplyToIsNotNull < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  INDEX_TABLE = :issues
+  INDEX_NAME = 'idx_on_issues_where_service_desk_reply_to_is_not_null'
+
+  def up
+    Gitlab::BackgroundMigration.steal('PopulateIssueEmailParticipants')
+    remove_concurrent_index_by_name INDEX_TABLE, INDEX_NAME
+  end
+
+  def down
+    add_concurrent_index(INDEX_TABLE, [:id], name: INDEX_NAME, where: 'service_desk_reply_to IS NOT NULL')
+  end
+end

db/schema_migrations/20210216223335

+52bf190bdb219366c790a5b7c081bfb383543498780cc95a25eafcecea036426
\ No newline at end of file

db/structure.sql

@@ -21355,8 +21355,6 @@ CREATE INDEX idx_mr_cc_diff_files_on_mr_cc_id_and_sha ON merge_request_context_c
 
 CREATE UNIQUE INDEX idx_on_compliance_management_frameworks_namespace_id_name ON compliance_management_frameworks USING btree (namespace_id, name);
 
-CREATE INDEX idx_on_issues_where_service_desk_reply_to_is_not_null ON issues USING btree (id) WHERE (service_desk_reply_to IS NOT NULL);
-
 CREATE INDEX idx_packages_build_infos_on_package_id ON packages_build_infos USING btree (package_id);
 
 CREATE INDEX idx_packages_debian_group_component_files_on_architecture_id ON packages_debian_group_component_files USING btree (architecture_id);