Either a MySQL server error (e.g. 'ER_ACCESS_DENIED_ERROR'),
a node.js error (e.g. 'ECONNREFUSED') or an internal error
(e.g. 'PROTOCOL_CONNECTION_LOST').
errno
errno:number
The error number for the error code
fatal
fatal:boolean
Boolean, indicating if this error is terminal to the connection object.
Either a MySQL server error (e.g. 'ER_ACCESS_DENIED_ERROR'), a node.js error (e.g. 'ECONNREFUSED') or an internal error (e.g. 'PROTOCOL_CONNECTION_LOST').