wp_ajax_nopriv_wpmdb_flush

See hook in action

See this hook used in plugins:

Select Pluginwp-migrate-db.1.0.2wp-migrate-db.1.0.3wp-migrate-db.1.0.4wp-migrate-db.1.0.5wp-migrate-db.1.0.6wp-migrate-db.1.0.7wp-migrate-db.1.0.8wp-migrate-db.1.0.9wp-migrate-db.1.0.10wp-migrate-db.1.0.11wp-migrate-db.1.0.12wp-migrate-db.1.0.13wp-migrate-db.1.0.14wp-migrate-db.1.0.15wp-migrate-db.1.0.16wp-migrate-db.1.0.17wp-migrate-db.2.0wp-migrate-db.2.0.1wp-migrate-db.2.0.2wp-migrate-db.2.1wp-migrate-db.2.1.1wp-migrate-db.2.1.2wp-migrate-db.2.2.0wp-migrate-db.2.2.2wp-migrate-db.2.3.0wp-migrate-db.2.3.1wp-migrate-db.2.3.2wp-migrate-db.2.3.3wp-migrate-db.2.4.0wp-migrate-db.2.4.1wp-migrate-db.2.4.2wp-migrate-db.2.5.0wp-migrate-db.2.6.1wp-migrate-db.2.6.3wp-migrate-db.2.6.4wp-migrate-db.2.6.5wp-migrate-db.2.6.6wp-migrate-db.2.6.7wp-migrate-db.2.6.8wp-migrate-db.2.6.9wp-migrate-db.2.6.10