I'm using queryAggregatedPoints and had the misfortune of specifying start/end time in between actual data points. The aggregate values coming back are unexpected. Here is the raw data:
"t_stamp","mypath"
"2026-06-09 22:33:11.861","8.100"
"2026-06-12 11:25:52.766","8.590"
"2026-06-18 09:51:12.169","8.319"
Floats shortened for readability. Here is my query:
data = system.historian.queryAggregatedPoints([tagPath, tagPath, tagPath, tagPath, tagPath, tagPath],
batch_start, batch_end,
aggregates=["Count", "LastValue", "Minimum", "Maximum", "Average", "SimpleAverage"],
columnNames=["Count", "LastValue", "Minimum", "Maximum", "Average", "SimpleAverage"])
print batch_start
print batch_end
print system.dataset.toCSV(data)
Fri Jun 12 11:26:00 CDT 2026
Tue Jun 16 18:21:00 CDT 2026
"t_stamp","simpleaverage","simpleaverage","simpleaverage","simpleaverage","simpleaverage","simpleaverage"
"2026-06-12 11:26:00.000","0.0","8.394","8.394","8.394","8.492","8.394"
You'll notice that the start time is just after raw point #2 and the end time is before raw point #3. The Count is 0, as expected. But the columns for LastValue, Minimum, and Maximum are returning the same value as SimpleAverage. These are user-entered values and I need the value as entered by the user, not an interpolated value.
The column names are also messed up, but I think that's a known bug.
If I pull the start time back so that raw point #2 is included in the start/end times, the results are as expected:
data = system.historian.queryAggregatedPoints([tagPath, tagPath, tagPath, tagPath, tagPath, tagPath],
system.date.addMinutes(batch_start, -60), batch_end,
aggregates=["Count", "LastValue", "Minimum", "Maximum", "Average", "SimpleAverage"],
columnNames=["Count", "LastValue", "Minimum", "Maximum", "Average", "SimpleAverage"])
print system.dataset.toCSV(data)
"t_stamp","simpleaverage","simpleaverage","simpleaverage","simpleaverage","simpleaverage","simpleaverage"
"2026-06-12 10:26:00.000","1.0","8.590","8.590","8.590","8.493","8.590"
This is on 8.3.7