SQLSTATE[HY000]: General error: 2006 MySQL server has gone away, query was.After placing order getting error
i am getting error below error after placing order:
SQLSTATE[HY000]: General error: 2006 MySQL server has gone away, query was: SELECT COUNT(*) FROM `sales_flat_order` AS `main_table` WHERE (main_table.customer_id = '12137') AND (state IN('new', 'processing', 'complete', 'closed', 'canceled', 'holded', 'payment_review')
How can I fix this error.