■ You must define a function before using it.
 
■ Possible solutions:
 
  • Verify that the name of the function you are calling
    is spelled correctly.
 
  • Use the DECLARE statement to declare the function
    procedure and invoke argument data-type checking.
 
  • Use the DEF FN statement to define the function.
 
■ If you need additional help, move the cursor to a keyword
  and press F1 to open the Help window.