ORA-FO-AVG-TYPES 15.3.2 fn:avg

*Functions and Operators, Section 15.3.2 fn:avg*

It has already been pointed out (in a reply to

http://lists.w3.org/Archives/Public/public-qt-comments/2003May/0243.html) 
that "date/time values" do not "support addition and division by an 
integer", and so cannot be avg'ed.

We would like to see a list of supported built-in types included in the 
definition of fn:avg.