
Python3 handles encoding differently, and files are loaded according to the locale set on the system. This means that when building on a locale-less chroot, the tests will always fail because it will try to load utf-8 and encode it as ASCII. This forces the encoding. The tests are encoded in utf-8 anyway so any other encoding set by the locale would cause a failure.
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.
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))
ρid➡i,name➡n(π a,b(A))
A ⋈ B
Run from sources
To launch the application, run
./relational_gui.py
If it needs some dependencies: Qt5, Python 3.4 or greater, PyQt5
It can run on osx but bugreports about that will be rejected.