Checking the max length field of data in the database

Posted this time I will try to explain how to check the number of length data field, the need to check length field data to recognize the need that the average user input how much for each input. For checking its quite simple by using the following query:

SELECT  name, LENGTH(name) AS max_length_name
FROM    mytable
ORDER BY
        max_length_name DESC
LIMIT 1

or examples

select max(length(Name)) 
  from my_table