How To Find Duplicate Values in MySQL

http://www.mysqltutorial.org/mysql-find-duplicate-values/

SELECT mem_name, COUNT(mem_name) FROM mem_password GROUP BY mem_name HAVING COUNT(mem_name) > 1

 

 

 

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compare row number and value form two different table

SELECT COUNT(member_info.mem_name) as milon, mess_info.mess_mem_num,mess_info.mess_name FROM member_info
INNER join mess_info on mess_info.mess_name=member_info.mess_name GROUP BY member_info.mess_name
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