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Relational an educational tool to provide a workspace for experimenting with *relational* *algebra*, an offshoot of first-order logic.
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It provides GUI that can be used for executing relational queries, and also provides a command line interface.
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Provides a standalone Python module that can be used for executing relational queries, parsing relational expressions and optimizing them.
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Official website
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================
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More documentation can be found here http://ltworf.github.io/relational/
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Install
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=======
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Binary download for Windows can be obtained from the website.
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For Linux, check your distribution's packages, relational is available on Debian and Ubuntu.
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Syntax
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======
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These are some valid queries
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```
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σage > 25 and rank == weight(A)
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σ (name.upper().startswith('J') and age>21 )(people)
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Q ⋈ π a,b(A) ⋈ B
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ρid➡i,name➡n(A) - π a,b(π a,b(A)) ∩ σage > 25 or rank = weight(A)
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π a,b(π a,b(A))
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ρid➡i,name➡n(π a,b(A))
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A ⋈ B
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```
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Run from sources
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================
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If it needs some dependencies:
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* Qt5
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* Python 3.4 or greater
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* PyQt5
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* pyuic5 and pyrcc5
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You will need to run
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```
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make
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```
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to generate some .py files.
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To launch the application, run
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```
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./relational_gui.py
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```
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Running on osx
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==============
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You can probably follow the instructions on running from sources to
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rut on osx.
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If you encounter problems, don't ask me for help.
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If you encounter problems and overcome them, please tell me how to update this
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README.
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