Searches the list of canvases and returns a canvas ID when it finds a valid canvas with the given name. You must define an appropriately typed variable to accept the return value. Define the variable with a type of Canvas.
FUNCTION FIND_CANVAS
(canvas_name VARCHAR2);
Built-in Type unrestricted function
Returns Canvas
Enter Query Mode yes
DECLARE
my_canvas Canvas;
BEGIN
my_canvas := Find_Canvas('my_canvas');
END;