mysql delete duplicate rows but keep one

1DELETE t1 FROM subscriptions t1
2INNER JOIN subscriptions t2 
3WHERE 
4    t1.id < t2.id AND 
5    t1.user_id = t2.user_id AND t1.name = t2.name

1DELETE FROM table_name WHERE id 
2       NOT IN ( SELECT id FROM table_name 
3                   GROUP BY field_1, field_2)

1DELETE c1 FROM contacts c1
2INNER JOIN contacts c2 
3WHERE
4    c1.id > c2.id AND 
5    c1.email = c2.email;

1DELETE FROM FriendsData WHERE fID 
2       NOT IN ( SELECT fID FROM FriendsData 
3                   GROUP BY UserID, FriendsUserID, IsSpecial, CreatedBy)
4

1DELETE FROM table_name 
2WHERE 
3	id IN (
4	SELECT 
5		id 
6	FROM (
7		SELECT 
8			id,
9			ROW_NUMBER() OVER (
10				PARTITION BY field_1
11				ORDER BY field_1) AS row_num
12		FROM 
13			table_name
14		
15	) t
16    WHERE row_num > 1
17);

1DELETE FROM NAMES
2 WHERE id NOT IN (SELECT * 
3                    FROM (SELECT MIN(n.id)
4                            FROM NAMES n
5                        GROUP BY n.name) x)