navicat删除表中重复数据的sql语句

DELETE FROM `hao123` WHERE ir_url IN
(SELECT ir_url FROM
(SELECT ir_url FROM `hao123` GROUP BY ir_url having count(ir_url)>1)a)
AND ir_id NOT IN
(SELECT * FROM
(SELECT min(ir_id) FROM `hao123` GROUP BY ir_url HAVING count(ir_url)>1)b);

hao123:表名。

ir_url:重复列名。

ir_id:在重复的列名中，保留ir_id值最小的，其余的删除，这样可以保证只留下一条数据。