I have amibroker 5.5 when I have Intraday data for suppose NCC script. from 20.3.2015 to 25.3.2015. Now when I backfill the data from external data feeder software (RT) to amibroker from 26.3.2015 to 30.3.2015 . It dont update it , it replace new data from old data. So data from 20 to 25march had been lost. What to do to keep both data in single database or it updates new data without deleting old data?