mysql 删除单表内多个字段重复的数据

DELETE from lot_log_payflow WHERE (pay_no,sub_flow_type) in   
(SELECT pay_no,sub_flow_type from (SELECT pay_no,sub_flow_type FROM lot_log_payflow GROUP BY pay_no,sub_flow_type HAVING COUNT(*)>1) s1)   
AND  
id NOT in (SELECT id from (SELECT id FROM lot_log_payflow GROUP BY pay_no, sub_flow_type HAVING COUNT(*)>1) s2);  

select * from lot_log_payflow  
WHERE (pay_no,sub_flow_type) in   
(SELECT pay_no,sub_flow_type from (SELECT pay_no,sub_flow_type FROM lot_log_payflow GROUP BY pay_no,sub_flow_type HAVING COUNT(*)>1) s1)   
AND  
id NOT in (SELECT id from (SELECT id FROM lot_log_payflow GROUP BY pay_no,sub_flow_type HAVING COUNT(*)>1) s2) order by create_time asc;  

DELETE from lot_order WHERE (order_no) in   
(SELECT order_no from (SELECT order_no FROM lot_order GROUP BY order_no HAVING COUNT(*)>1) s1)   
AND  
id NOT in (SELECT id from (SELECT id FROM lot_order GROUP BY order_no HAVING COUNT(*)>1) s2);