Relational an educational tool to provide a workspace for experimenting with relational algebra, an offshoot of first-order logic.

It provides GUI that can be used for executing relational queries, and also provides a command line interface.

Provides a standalone Python module that can be used for executing relational queries, parsing relational expressions and optimizing them.

Install

Windows installer can be found here: https://code.google.com/p/relational/downloads/list

For Linux, check your distribution's packages, relational is available on Debian and Ubuntu.

Syntax

These are some valid queries

σage > 25 and rank == weight(A)
σ (name.upper().startswith('J') and age>21 )(people)
Q ᐅᐊ π a,b(A) ᐅᐊ B
ρid➡i,name➡n(A) - π a,b(π a,b(A)) ᑎ σage > 25 or rank = weight(A)
π a,b(π a,b(A))
ρid➡i,name➡n(π a,b(A))
A ᐅᐊ B

Formal language definition at this link https://github.com/ltworf/relational/wiki/Grammar-and-language

Run from sources

To launch the application, run

./relational_gui.py

If it needs some dependencies: Qt4, Python 2.7, either PyQT4 or Pyside.

It can run on osx but this is not supported.