Hello,

from the documentation:

http://www.kentico.com/docs/devguide/index.html?sql_queries_debugging.htm

If you want to use SQL debugging on ASPX page templates, you need to manually add the following control to the page. It will display the same queries table as in the Live site mode debugging described above.

<cms:QueryLog ID="logQuery" runat="server" />

But when I try to use it:

Unknown server tag 'cms:QueryLog'.