How about if I have this table?
From this layout:
Hostname MACAddress
Computer1 MACAddress1
Computer1 MACAddress2
Computer2 MACAddress3
Computer3 MACAddress4
Computer4 MACAddress5
Computer4 MACAddress6
To this layout:
Hostname MACAddressA MACAddressB
Computer1 MACAddress1 MACAddress2
Computer2 MACAddress3 NULL
Computer3 MACAddress4 NULL
Computer4 MACAddress5 MACAddress6
Any...