Specifying Cursor SQL

I am just learning about PL/SQL.

 From what I've read so far (John Palinski's book - I don't know how well it stands up against other publications, but it's done sterling service for me with respect to the Oracle SQL I've been doing the past few years), there doesn't seem to be an easy way of passing an SQL select statement to a function or procedure.

Here's what I'm trying to do (please note I've prefixed -- with an apostrophe for those whose newsreaders format .sig files differently from the post's main body):

create or replace function F_DISTRIB
(SQL_STATEMENT in varchar2(32000))
return number is
/*

SQL_STATEMENT is a select statement which results in anything from a simple single value to a complex construction that returns multiple values.

I specified varchar2(32000) as I don't think I can just leave things open ended with specifying it as just varchar2 without a length specification?

*/
'--

n_Distribution number;
cursor cDistributions is

    select
     DIST_VALUE
    from
     SOME_TABLE
    where
     SOME_COLUMN IN (SQL_STATEMENT);
'--

begin
'--

   open cDistributions;
     <run through records which add decimal values to n_Distribution>    close cDistributions;
'--

   return n_Distribution
'--

End

The thing I'm trying to do is pass the SQL statement to the cursor to be used in the cursor's where clause.

AFAIK, the above is not the way to do it. Could I please ask for some site, perhaps, that might explain how to use SQL in a dynamic way as I've tried to do up above?

Thanks very much in advance.

-- 
Tim    http://www.ucs.mun.ca/~tmarshal/
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