An in-process analytics database, DuckDB can work with surprisingly large data sets without having to maintain a distributed multiserver system. Best of all? You can analyze data directly from your Python app.
pg_timeseries is an open-source PostgreSQL extension focused on creating a cohesive user experience around the creation, maintenance, and use of time-series tables. It allows users to create time-series tables, configure the compression and retention of older data, monitor time-series partitions, and run complex time-series analytics functions with a user-friendly syntax.
Catena uses a Blockchain based on SHA-256 hashes for proof of work, with configurable difficulty. Blocks contain transactions which contain SQL statements. Catena is written from scratch and is therefore completely different from Bitcoin, Ethereum etc.