To use the MEAN Function
MEAN(Tag,Tag,Tag)
The mean is found by adding up all of the given data and dividing by the number of data entries
Tag1 + Tag2 + Tag3 / 3
MEAN(Demo-influxdb/DEMO_01TI031.PV,Demo-influxdb/DEMO_01TI032.PV,Demo-influxdb/DEMO_01TI021.PV)
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