help on "the" operator

Hi Gurus!
 if any function which returns the collection type , to show that collection object in tabular format we use "the" operator with dual table which has one row and one column like followings:  select * from the
(select cast( <<function name l(parameters )>> as <<return obeject type>> ) from dual )

my question is can i use any real table in my existing database other than "Dual" in above SQL . Does "the" operator looks for single records in inner SQL ( as returning records from dual does mean that single record and single column ) i means to say when i use real table then it gives the error   "ORA-01427 : single row subquery returns more than one row " i hope the operator looks for only one record . If it is that then can access the result wot i want by using real table because the parameters which r being passed in function are columns from the table wot i want to use ? looking for help.........
thanx in advance

Shishir Kumar Mishra
Agni Software (P) Ltd.,
Bangalore-560055, India
www.agnisoft.com

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Author: Shishir
  INET: shishir_at_agnisoft.com

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