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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.
6a. Even stricter option is an "append-only" aka "timeseries" schema, which I highly recommend. Can't remember the last time I didn't use one.
7. If you happen to be testing on a Mac, https://postgresapp.com/ is easier than the MacPorts or Homebrew packages.
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