Changing old data for rrd4j via openHAB is not possible. The reason is simply the way data is stored in rrd4j. This persistence uses “archives” to store data for different timeranges (for example: the last day, the last 7 days, the last xx days…). Each data request is fetched from that archive that covers the whole requested timeframe.
In other words for a specific timepoint there migth be data in more then one archive. ( data for now-4 hours would be in the archive of the last day, the last seven days…).
Changing such a datapoint correctly later is rather “complicated”.I had posted a way to change indivdual datapoints “by hand” in a rather old post. However setting all affected archives correctly that way remains “complicated”.
Old post
