How to close the connection to MYSQL in nodejs node-mysql

It seems that sometime the connection to MYSQL not closed succeed. I am using nodejs and node-mysql library.

client = mysql.createClient({ user: 'root', password: 'pass' });
client.query('USE db');
client.query( 'SELECT a FROM b ORDER BY c ASC', function selectCb(err, results, fields) {
  client.end();
  if (err) throw err;
  ....       
});

Hope that helps!

client.end(function(err) {
    // do what you want after the connection if closed :)
});

Also you can check this link : https://github.com/felixge/node-mysql#pooling-connections`