2006 - MySQL server has gone away

select r.reviews_id, r.reviews_rating, p.products_id, p.products_image, pd.products_name from reviews r, reviews_description rd, products p, products_description pd where p.products_status = '1' and p.products_id = r.products_id and r.reviews_id = rd.reviews_id and rd.languages_id = '2' and p.products_id = pd.products_id and pd.language_id = '2' order by r.reviews_id desc limit 10

[XT SQL Error]

2006 - MySQL server has gone away

select count(*) as total from sessions where sesskey = '35dcdb2670a3deb2fee64a248b3be987f3f5b801'

[XT SQL Error]