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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.
You can even find smaller (and cheaper and less powerful) devices than RPi which are able to do that – e.g. https://github.com/espressif/esp-who for ESP32-CAM (~$10). Usage of that library is also very straightforward, there are many examples on the internet.
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