Arel is a Relational Algebra for Ruby. It 1) simplifies the generation complex of SQL queries and it 2) adapts to various RDBMS systems. It is intended to be a framework {framework;} that is, you can build your own ORM with it, focusing on innovative object and collection modeling as opposed to database compatibility and query generation.

WWW: https://www.rubygems.org/gems/arel
