SQL & PL/SQL

Hi All,

I have created a PL/SQL fuction in the database as shown below:

Create or replace function balance_check(surname IN varchar2)

return number is

totalsales number(12,2);

BEGIN

select total_sales into totalsales from customer where surname = surname;

return totalsales;

END;

/

Now, I want someone to show me how to execute this function from the SQL prompt. I have tried doing this but hard errors anytime I tried.

Thanks in advance.