Datalog Notes

The Datalog problems on Assignment #4 are small enough that they can be done without the use of a Datalog system. However, it's much more fun to actually write and test your Datalog queries with a real system! So here are some pointers to systems that you can install and use to get some hands-out experience. (Those doing ECS-165B will see a little bit more of Datalog next quarter!)

Datalog Educational System (DES)

[DES-Datalog site] This is a comprehensive Datalog system, with support not just for full-fledged Datalog (with aggregation etc), but it also supports SQL and Relational Algebra queries. It has lots of example code, nice documentation etc. Good fun! The TA will show this in the discussions sections! Some downsides: It's not meant for Big Data!

Beware the DES-Datalog syntax for negation / "not" ! A possible source of confusion / "gotcha" !

DLV Datalog/AI System

[DLV-Datalog site] This is not just a Datalog system, but more of an AI/KR (Artificial Intelligence/Knowledge Representation) system as well. One can download binaries for different platforms. This is more of a research vehicle, but will also get the job done of playing with Datalog for your homework assignment.  

Whether you use DES-Datalog (recommended) or DLV-Datalog: for details of the syntax, please refer to the respective manuals!