Hi Driller,

Thanks for the suggestion. Why didn't I think of that? It works for simple
DSUM. I have a couple of Data Validation Dropdown lists that get their data
from dynamic ranges, referencing the sheets of data described. I have tried
adding the range names from both sheets together in the "refers to" field on
the define range box to create a third spanning range by combining the two
sheet ranges. It works for spanning ranges for a value list in a drop down
list.

I tried using that same method for the database in a DSUM but no dice. Seem
like it has to create some kind of huge array calculation in the background
that takes forever (judging from the result in the formula auditing).

Anyway, looks like this will work. I still have to work out a spanning
DAVERAGE but I guess this will be something like the product of the daverages
of the two sheets.

Thanks,
RDW

"driller" wrote:

1. considering that the number of columns (256) is not critical
2. the number of rows of record is not enough, need to extend in another
sheet.

based on my few test of Dsum, only

a. on mainsheet where your formula Dsum is located along with the criteria
on the top rows.

b. on 2nd,3rd.... sheets where your inventory range can be located as
extension.
where row 1 must contains the same text column title
then define another name like "inventory2" for 2nd sheet
range..."inventory3" for 3rd sheet range....

formula for DSUM on the mainsheet.
=dsum(inventory,"qty",O20:R21) + dsum(inventory2,"qty",O20:R21)
this will extend the inventory range by just classically summing the sheets
you need.