How to delete duplicate records in mysql?

Find Duplicate entries :

SELECT Count(*) as cnt
, col1, col2  FROM 
table_name GROUP BY col1, col2
 HAVING Count(*) > 1

Remove Duplicate entries:

Approach 1:

DELETE FROM table_name 
USING table_name, table_name AS t1
WHERE 
    (table_name.id > t1.id) 
AND (table_name.col1= t1.col1 ) AND (table_name.col2= t1.col2 )

Note:  Here id is identity column (Auto increment column)

and Replace col1, col2 and table_name

Approach 2: 

DELETE t3
FROM (
        SELECT t1.col1, t1.id
        FROM (
                SELECT col1
                FROM table_name
                GROUP BY col1
                HAVING COUNT(col1) > 1
        ) AS t0 INNER JOIN table_name t1 ON t0.name = t1.name) AS t2 INNER JOIN table_name t3 ON t3.name = t2.name
WHERE t2.id < t3.id;