relational/README.md

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

It works on GNU/Linux, Windows and OS X.

It provides:

  • A GUI that can be used for executing relational queries
  • A standalone Python module that can be used for executing relational queries, parsing relational expressions and optimizing them
  • A command line interface

Official website

More documentation can be found here http://ltworf.github.io/relational/

Install

Binary download for Windows can be obtained from the website.

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 ⋈ π a,b(A) ⋈ B
ρid➡i,name➡n(A) - π a,b(π a,b(A)) ∩ σage > 25 or rank = weight(A)
π a,b(π a,b(A))
ρ id➡i,name➡n(π a,b(A))
A ⋈ B

Run from sources

If it needs some dependencies:

  • Qt5
  • Python 3.4 or greater
  • PyQt5
  • pyuic5 and pyrcc5

You will need to run

make

to generate some .py files.

To launch the application, run

./relational_gui.py

or

python3 relational_gui.py