That is correct. We are somewhow managing to find the differences. Let describe the file structures:
a. All the files consist of 6 columns (product, description, price, discounts, date available and store available)
b. There are about 200 rows (that means there are 200 products listed in each row)
c. The difference in these groups of files can occur anywhere in the product column, price column or discount column.
d. We pick up two files (say A and B); paste file B's contents below those in A; then run ASAP utilities (duplicate / unique records finder)
e. If ASAP utilities report everything to be duplicate, we assign B to group A
f. If ASAP utilities report difference(s) between A and B contents, we assign file B to group B
g. Then we pick up file C and repeat this procedure - twice if A and B HAD BEEN identified different from each other. Now file C can go to group A, or group B or make its own group C. Now that we know there will be only four groups, files E onwards will have to be compared to A, B, C and D.
And we are definitely not proud of this donkey work.
We tried some 'duplicate file finders' in the market, but none could really report precisely.
It takes 3-4 staff members eating up 2-3 hours for this otherwise innocuous looking stuff.

Arvind