Tutorial :prolog to SQL converter


Without thinking to much, it seems to me that a large set of Prolog's functionality could be implemented as relational calculus (a.k.a. SQL).

Has anyone heard of any tools to automatically convert Prolog to SQL?




my advice- use Eclipse prolog (http://www.eclipseclp.org/) (not (here) to be confused with prolog in the eclipse IDE).

I spent hours trying to get the code to compile in 4 other prologs(!) and 4 minutes to compile in eclipse.

When it works, it's a thing of beauty.

Credit to Herr Draxler of course


Yes, of course.

A premise for skeptics: any semi-decent book on database theory mentions Datalog (which is Prolog-like) and theorems which demonstrate that is possible to translate it to/from Relational Algebra (RA) (under specific restrictions).

SQL is not faithful to RA or relational calculi, but is enough to support Prolog:


The mapping isn't very good. SQL, for example, doesn't do backtracking, unification, lists, or adhoc nested structures.

Prolog doesn't deal well with composite objects, indexes, etc.

I'd say it's a no-go.


It makes more sense to do an sql query from prolog, which can then be translated into prolog facts. e.g. Prolog ODBC Library

This removes all restrictions and keeps the two languages separated into their proper places.

Note:If u also have question or solution just comment us below or mail us on toontricks1994@gmail.com
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