delete all duplicate rows keep the latest except for one in mysql code example

Example 1: mysql delete duplicate rows but keep one

DELETE c1 FROM contacts c1
INNER JOIN contacts c2 
WHERE
    c1.id > c2.id AND 
    c1.email = c2.email;

Example 2: how to delete all duplicate items in mysql

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

Example 3: delete all duplicate rows keep the latest except for one in mysql

DELETE 
FROM
  `tbl_job_title` 
WHERE id NOT IN 
  (SELECT 
    * 
  FROM
    (SELECT 
      MAX(id) 
    FROM
      `tbl_job_title` 
    GROUP BY NAME) tbl)