Alf is a modern, powerful implementation of relational algebra. It brings relational algebra where you don’t necessarily expect it: in shell, in scripting and for building complex software. Alf has an rich set of features. Among them, it allows you to:
Query .json, .csv, .yaml files and convert from one format to the other with ease,
Query SQL databases with a sounder and more powerful query language than SQL itself,
Export structured and so-called “semi-structured” query results in various exchange formats,
Query multiple data sources as if they were one and only one database,
Create database viewpoints (mostly read-only viewpoints for now), to provide your users with a true database interface while keeping them away from data they may not have access to,
Enjoy a rich set of relational operators and even define your own high-level and domain-specific ones.