hello,

I have thousands of records in my table: in column A many duplicate values, I would need to get only those unique values from column A which have different values in column B (ignore the same values in column B for corresponding value in A):

A B
1 a
1 a
2 b
2 b
2 c
3 d
3 d
4 a
4 b

so as a result from example above, I should get only 2 and 4 on my list.
I was browsing for couple of of hours but couldn't find any solution. I guess loop is needed, but I am quite novice.

thanks