如何用MySQL数据库的LEFT JOIN？

SELECT o.phone,n.presenter_uid,COUNT(*) as counts FROM ziroomer_ldx_new_list n LEFT JOIN ziroomer_ldx_old_list o ON o.uid = n.presenter_uid WHERE n.customer_type = 1 GROUP BY n.presenter_uid ORDER BY counts DESC limit 100 

SELECT o.phone,n.presenter_uid,COUNT(n.id) as counts FROM ziroomer_ldx_new_list n,ziroomer_ldx_old_list o WHERE n.customer_type = 1 AND o.uid = n.presenter_uid GROUP BY n.presenter_uid ORDER BY counts DESC LIMIT 100;