Clearing zabbix history via SQL

DELETE FROM history_uint WHERE clock < UNIX_TIMESTAMP(DATE_SUB(NOW(), INTERVAL 2 DAY));
DELETE FROM history WHERE clock < UNIX_TIMESTAMP(DATE_SUB(NOW(), INTERVAL 2 DAY));
DELETE FROM trends_uint WHERE clock < UNIX_TIMESTAMP(DATE_SUB(NOW(), INTERVAL 2 DAY));
DELETE FROM trends WHERE clock < UNIX_TIMESTAMP(DATE_SUB(NOW(), INTERVAL 2 DAY));
DELETE FROM events WHERE clock < UNIX_TIMESTAMP(DATE_SUB(NOW(), INTERVAL 2 DAY));
DELETE FROM alerts WHERE clock < UNIX_TIMESTAMP(DATE_SUB(NOW(), INTERVAL 2 DAY));