Altho connect_cached() looks nice, I'm still not sure I should be using it.
Programming the Perl DBI lists it as (NEW) and also states 'it can also cause problems and should be used with care. The exact behaviour of this method is liable to change'.

To answer your question (which you then took back), the number of requests made depends on the usage of the application.

Greetz
Beatnik
... Quidquid perl dictum sit, altum viditur.