# See http://doc.gitlab.com/ce/development/migration_style_guide.html# for more information on how to write migrations for GitLab.classAddIndexOnCiRunnersContactedAt<ActiveRecord::MigrationincludeGitlab::Database::MigrationHelpers# Set this constant to true if this migration requires downtime.DOWNTIME=falsedisable_ddl_transaction!defupadd_concurrent_index:ci_runners,:contacted_atenddefdownremove_concurrent_index:ci_runners,:contacted_atifindex_exists?(:ci_runners,:contacted_at)endend