A have a table with a pair of columns. I need remove the rows where the combined column 1 and column 2 is already in the table with column 2 and column 1. Easier to explain by example. Say this is the table:
COLUMN1 COLUMN2
ITEM-A ITEM-1
ITEM-B ITEM-2
ITEM-1 ITEM-A
I would like to remove the third line in the table (ITEM-1, ITEM-A) because that combination of values is already in the table in line 1 - just reversed order. I've been trying to work out a process using a column rename and SET operations and trying to figure out a way to use the loop process but no luck so far.
Any ideas how to do something like this?