Sorting and null for monetary values in a report

Question

All,
I think this should be an easy one, and I've just missed something obvious.
I have a standard report in APEX 3.2.1 that includes a column with a monetary amount in it. I want the column to show the UK Pound sign, be sortable, and show nulls where appropriate.
The issue I have is I can't find a way to achieve all 3 in a satisfctory way. As I see it the options would be:
1) In the SQL for the report, concat the pound sign to the column required, e.g. SELECT '£'||amount FROM....
The issue is that this makes this field a CHAR field, so sorting would not sort in the same way as for a number field.
2) Use the Number format FML999...etc. in the Column Attribute.
The problem with this is that this is a multi-country database, and the default monetary unit is set to the US dollar.
3) Use the HTML expression box in the Column attribute to display £#COL#
This fulfills the pound sign and retaining the number format, but unfortunately a null value is displayed as a £ sign with no numbers. I can't think how to get it to leave that value in the report as completely blank.
As I said, I'm sure I've missed soemthing obvious. If anyone can spot how to achieve this it'd be much appreciated.
Regards,
Jon.

Answer 1

>
2) Use the Number format FML999...etc. in the Column Attribute.
The problem with this is that this is a multi-country database, and the default monetary unit is set to the US dollar.
>
The NLS currency symbol can be modified on the fly if you have some means of identifying user location/preference: {thread:id=990848} (ignore the last post)
However, it probably doesn't make sense to do that—£100 ≠ $100 (at least I hope not!)—unless there's some kind of conversion occurring in the report? Is there a currency stored along with the amount?
>
3) Use the HTML expression box in the Column attribute to display £#COL#
This fulfills the pound sign and retaining the number format, but unfortunately a null value is displayed as a £ sign with no numbers. I can't think how to get it to leave that value in the report as completely blank.
>
Use 2 columns, one for the amount, and one for the currency, with a switch to include or exclude the latter as necessary:
select
          ename
        , comm amount
        , nvl2(comm, '£', null) currency
from
          emp
where
          job in ('SALESMAN', 'MANAGER')
ENAME      AMOUNT                 CURRENCY                        
ALLEN      300                    £                               
WARD       500                    £                               
JONES                                                             
MARTIN     1400                   £                               
BLAKE                                                             
CLARK                                                             
TURNER     0                      £                                Then use both columns in the Amount HTML Expression:
#CURRENCY##AMOUNT#