2013 - Lost connection to MySQL server during query

select count(*) as total from reviews r, reviews_description rd where r.products_id = '364' and r.reviews_id = rd.reviews_id and rd.languages_id = '2' and rd.reviews_text !=''

[XT SQL Error]

2006 - MySQL server has gone away

select count(*) as total from sessions where sesskey = 'k38j75k8pd4sbtcbg1ll2jcdb4'

[XT SQL Error]