2013 - Lost connection to MySQL server during query

SELECT max(quantity) as qty FROM personal_offers_by_customers_status_1 WHERE products_id='6' AND quantity<='1'

[XT SQL Error]

2006 - MySQL server has gone away

select count(*) as total from sessions where sesskey = 'f234c8d5844719d587c76658375582dc'

[XT SQL Error]