MyBB SQL Error

MyBB has experienced an internal SQL error and cannot continue.

SQL Error:
2006 - MySQL server has gone away
Query:
REPLACE INTO mybb_datacache SET `title`='internal_settings',`cache`='a:1:{s:14:\"encryption_key\";s:32:\"ZEN88AVvamfsBQexntCVLJZsgIjy5XJr\";}'