I need to do a op that update multiple records into a DB, what's is the best way to do it? using dataset or commandbuilder?

CustomBuilder is the fast and easier way, but if you want better control, you may want to consider using the other method instead.

Rgd

The commandbuilder is easier, but it also only works with single-table updates. If you are joining multiple tables, looping through a dataset may be your best option.