#查重：
Select * From 表名 Where 字段名称 In (Select 字段名称 From 表名 Group By 字段名称 Having Count(*)>1)
 

#删除重复数据只留其中一条

DELETE FROM 表名 where id not in (select id from (select min(id) as id from 表名 group by 字段名称) as b ) ;
 
select * 
FROM 
tpaas_corp2 
WHERE 
corp_name IN ( 
SELECT 
t.corp_name 
FROM 
( 
SELECT 
corp_name 
FROM 
tpaas_corp2 
GROUP BY 
corp_name 
HAVING 
count(1) > 1 
) t 
) 
AND id NOT IN ( 
SELECT 
dt.minid 
FROM 
( 
SELECT 
min(id) AS minid 
FROM 
tpaas_corp 
GROUP BY 
corp_name 
HAVING 
count(1) > 1 
) dt 
)