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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.
https://8weeksqlchallenge.com here is a fun and well organized program for working on your SQL skills. All the answers are provided if you need them. It starts off pretty light weight so you can warm up to it. Working on sites like Leetcode, Hackerrank, Stratscratch will only lead to headaches. Those are poorly written questions that are more for reading comprehension than learning SQL.
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