Relational 2.5 could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this software available. This PC software can be installed on 32-bit versions of Windows XP/7/8/10/11.
Commonly, this program's installer has the following filename: relational_gui.exe. The most popular versions of the Relational 2.5, 2.1 and 1.2. Relational is included in Education Tools.
We cannot guarantee that the program is safe to download as it will be downloaded from the developer's website. Before launching the program, check it with any free antivirus software. This free software is an intellectual property of Salvo 'LtWorf' Tomaselli.
From the developer:
Relational is an educational tool that provides a workspace for experimenting with relational algebra. The program provides a GUI that can be used for executing relational queries, and a command line interface. Also, it includes a standalone Python module that can be used for executing relational queries, parsing relational expressions and optimizing them.
You may want to check out more software, such as EPiServer Relate, PostgreSQL or MapRelate, which might be similar to Relational.
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