Replaces one or more fields with a new field and computes a hash value of these fields
Merge two fields into a hash value
{ "timestamp":1586380104915, "mass_flow":4.3167, "temperature":40.05, "sensorId":"flowrate01" }
{ "timestamp":1586380104915, "sensorId":"flowrate01" "demo":"8ae11f5c83610104408d485b73120832", }