New to report painter - what is 8A-A-PL

Question

Gentleman,
I am new to Report painter but have a fairly modest report to build, so I went into building it:
I have copied     PCA standard report   8A26-001   from report group 8A2.
I want nothing more than the output of the standard report, but organize differently (lines in  different orders) and with subtotals.
I was expecting to be able to list the desired accounts in the Characteristic values.
The std report lists 'Account number'   from  ''8A-A-PL '' to ..
Can one of the gurus be kind enough to explain to me what this is, and ideally, if I am on the wrong track?
KR -  Loïc
Moderator: Please, search SDN and read help.sap.com on Report Painter

Answer 1

Juan, be aware that returning null won't work with value types, such as an int, which can't be null. You'd have to use a nullable value type. A nullable int would be declared with a "?", such as:
int? someOtherFunction(int param)
if(something goes great)
return param * 42;
return null;
And you have to use it like this:
int? result = someOtherFunction(666);
if (result != null) // you can also use result.HasValue
// it worked, do something with the result
// if you're doing math with the result, no problem
int x = result * 2;
// but if you're assigning it to another an int, you need to use this syntax
int y = result.Value;
Before nullable value types came along, for a method that returned an int, I'd use a value of something that wouldn't normally be returned by that method to indicate failure, such as a -1.
~~Bonnie DeWitt [C# MVP]
That's something very very important to keep in mind. Can save you from a lot of headaches!
So if you have an int function and it might return NULL, if you are doing Math with the return value you can use it directly, but if you're assigning it to another variable you have to use .Value?
Thanks