I have an interesting problem. I have the data in the following
format:

a1|b1|c1|d1|__|__|
a1|b1|__|__|e1|f1|
a2|b2|c2|d2|__|__|
a2|b2|__|__|e2|f2|


and I'd like to be able to merge the rows based on the values in the
first two columns. So the above table would become:

a1|b1|c1|d1|e1|f1|
a2|b2|c2|d2|e2|f2|

I have a large file in this format, where I must merge 2,3 or
sometimes 4 rows in this fashion.

Anyone ?