Kdb+ uses Lambda architecture has the following properties:
- Data currently using stores in memory, while historical data is stored on disk.
New data come in from streaming sources.
Event-engine distribute data to downstream subscribers, including real-time database engine and streaming query engine.
Real-time database projects its content down to on-disk historical database for analytic use at daily basis, controlled by event-engine.
https://github.com/KxSystems/kdb
Kx Systems
1998
kdb
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