user functions in SQL-Server 2000

can anyone show me how to call a function with ADO.


The function
turn_over(cust_no, periode, year, currency, type)

is called as
SELECT dbo.turn_over(825, 201, 2000, 'EUR', 'N') AS turn_over

in the moment i use a TAdoQuery with:

Sql.Text := Format('select dbo.turn_over(%d, %d, %d, ''%s'', ''%s'') AS
turn_over', [825, 201, 2000, 'EUR', 'N']);

With this Solution i have no possibility to store the SQL-Statemant in the
database. ( i do this with all
other SQL Statements)

How can i use Parameters as i use them when calling a procedure?

Thanks for your support

Knut Lambert