resources and resource types

When I did a search on "resource(5)" within the PHP online documentation, I found the resource page resource.php. While although it lists all the resources used with mysql, it does not mention how resources are related to resource numbers as above. A query such as a row count on a table results in an integer value.  What is the best way of accessing or converting the integer value from the resource? I can't see any particular function in the function list which does this, without getting into strings or arrays, or have I missed something blaringly obvious, hope not?