Add flag for offline archive reprocessing to honor archived digital state values
If a tag is edited to use a new digital state set, this set will be used for all future data even though the previous state set is still used for historical data. If a historical archive (prior to editing the digital state set used by the point) is reprocessed, the events within the archive will be coerced to the new digital state set. This can be very confusing if the archived data is intended to be the old digital state set.
Bryan Klosiewicz commented
This makes manageability very difficult whenever a customer wants to merge or split a large enterprise PI system. My customer wanted to split their centralized PI system into individual business unit systems due to many years of growth which led to decreasing performance.
The issue is that reprocessing an archive honors the digital state set in the header of the archive file and doesn't honor any digital state set changes made along the way. The only way to avoid this is to only 'append' to the original digital state set and avoid any string replacements for a given integer value (eg - 1 = OPEN changed to 1 = CLOSED).
This is a major issue as customers such as utilities go through their backend SCADA system upgrades which occur every 10 years or so. Often the SCADA vendor dictates these digital state sets which can vary wildly from previous sets.