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InfluxDB
Power Real-Time Data Analytics at Scale. Get real-time insights from all types of time series data with InfluxDB. Ingest, query, and analyze billions of data points in real-time with unbounded cardinality.
There is https://qelectrotech.org/. I've toyed around with it a bit, but haven't tried using it for anything serious. I can't speak for how good it is, but it looks likes it could be ok if you are on a budget.
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