MySQL Server has Gone Away in Drupal 7

Question

In my form field type, i edit the file menu these error will appear,

Fatal error: Uncaught exception \'PDOException\' with message \'SQLSTATE[HY00

Answer 1

This may be because of max_allowed_packet

Change in the my.ini/my.cnf file. Include the single line under [mysqld] in your file

max_allowed_packet=500M

now restart the MySQL service once you are done. You can see it's curent value in mysql like this:

SHOW VARIABLES LIKE 'max_allowed_packet'

You can read about it here http://dev.mysql.com/doc/refman/5.1/en/packet-too-large.html