PipelineDB - The Streaming SQL Database

An open-source relational database that runs SQL queries continuously on streams, incrementally storing results in tables. PipelineDB stores only the output of continuous queries, which are incrementally updated as data is ingested. The database’s size is independent of the amount of data ingested over time. It is built into the PostgreSQL core and can be used as a drop in replacement for PostgreSQL without making any application code changes.