mysql field length

Question

How do I find the longest value in my mysql table?

I have a php script and I want to search my table to find the record with the longest string?

Any ideas?

Answer 1

You can use the mysql command LENGTH()

<?php 
$q = mysql_query("SELECT LENGTH(yourfield) AS fieldlength FROM yourtable ORDER BY fieldlength DESC LIMIT 1"); 
echo $longestfield = mysql_result($q,0); 
?>

Answer 2

MySQL has a lot of string functions you can use:

SELECT LENGTH(col) as my_len FROM my_table ORDER BY my_len DESC LIMIT 1

More funky version (it works):

SELECT MAX(LENGTH(col)) FROM my_table

Answer 3

It wasn't your original question, but if you are seeking the maximum length to help you with table the definition, you should check out PROCEDURE ANALYSE():

http://dev.mysql.com/doc/refman/5.0/en/procedure-analyse.html