Thanks for your details explanations @kevinadi
Like @Gorkem_Erdogan I was assuming timeseries collections would have a mechanisms to ensure uniqueness of timestamp/sensor data.
It’s clearly a must have features for time series as network unstable connectivity may cause data to be sent multiple times.
I think I’ll go with this suggestions of querying data only through aggregation pipeline with a group stage to remove duplicates.
But it has impact in performance and complexity of development…