But... in at the least two circumstances this option is useful: backfilling extra bars just after options adjust (when you enlarge 'number of bars to load' in File->Database Configurations dialog It's important to pressure backfill for symbols that were backfilled Beforehand with scaled-down variety of bars) cleaning up lousy ticks https://angelofgfca.blogtov.com/15650463/amibroker-data-fundamentals-explained