Which two statements about the Data Update process are true? $($Choose two.$)$

Choose $2$ answers

A$.$ A full data update process requires that all data files for a data source be presented.

B$.$ The net change data update process does not require an extract.done file.

C$.$ The net change data updates require that the customer has written a net change extract program.

D$.$ In a full data update, a record that is missing in the data files indicates a deletion.