Hi
I think, you should use table buffering in this case. Since it just invlove one table. You also can use view if that involve more than one tables.

Use GETNEXTMODIED() before tableupdate in a loop to get the record no of changed record. Compare each fields value with CURVAL() and OLDVAL() to detect changes. If OLDVAL() # CURVAL(), it meant record changed by other. Prompt user or do whatever necessary.

check out TABLEUPDATE() for more information about update method, either update all or none... or ... update not changed record and remain those changed record.

HTH