We are accessing a data file that has multiple timestamps for various data points. The file is updated at irregular intervals with multiple data readings which means I can't just fnd the last entry for a data point and add that to the archive, as I may have missed previous data.
For example, I have a data file which returns data at midnight every day for a data source. However, the data file is updated every 3-4 days, which means I need to add the midnight data for the intervening days, not just the latest midnight value. I can read the entire data file and just store duplicate data for the days already recorded, but I don't want to have multiple values for the same date/time (arc no-replace I think it's called in OPC data collection). Is there a way to either filter out the data already in the Data archive, or to just overwrite the data archive values so I don't have multiple values at the same timestamp everytime the file is updated? (does that make sense?)
