time query?

How i can know the time of a query?
i use Xquery with tamino xml server 4.1.4.1 evaluation version on windows 200 advanced server, how i can see the time of response of a query? or exist some aplication for that?

the function _duration=on is to X-Query, i have a query but i don´t work:

http://localhost/tamino/xml/Estudiantes1010/ficha?_XQL=/ficha[//nombrePrincipal=‘Pedro’]
the result is :

<?xml version="1.0" encoding="ISO-8859-1" ?>

when i use _duration=on dont show the result of query
http://localhost/tamino/xml/Estudiantes1010/ficha?_duration=onXQL=/ficha[//nombrePrincipal=‘Pedro’]
the result is :

<?xml version="1.0" encoding="ISO-8859-1" ?>

how is the correct sintaxis of the query to i can see the result and the time?

if exist some method (program) to show the response time or documentation (in X-Machine is very poor)
Thanks

As you are using a URL based access you need to separate parameters with an ‘&’:

http://host/tamino/db?_duration=on&_xql=