Update table value

[Howdy1]

Hi, I am trying to update a group value based on certain criteria. Currently, there are 1926 records and I need to group the records based on different field value. If the account is the same with a group of different FSItem, then it will be group into one group. The account doesn't have to be the same for the group, as long as the FSItem are the same.
Please refer to the following examples. Any good idea to code the logic instead of manually updating it? Thanks a lot!

---------------before the update ----------
AcctCode --- FSItem ---- GroupName
1234 ----------123 --------
1234 --------- 124 --------
1234 --------- 125 -------
1235 --------- 125 -------
1235 --------- 126 -------

********after the update ********

AcctCode --- FSItem ---- GroupName
1234 ----------123 -------- Group1
1234 --------- 124 -------- Group1
1234 --------- 125 ------- Group1
1235 --------- 125 ------- Group2
1235 --------- 126 ------- Group2
----------------------------------

 

[Fazza]

Hi, Please can you give some further explanation? It isn't clear what is required. Regards, F