Material this week:
Query resolution (SLD resolution) on definite databases – building query trees / evaluating
The Datalog Educational System can be downloaded for most platforms – the Windows executable can use the ODBC interconnectivity layer to connect to Access database files.
Some of the query resolution material (in a different form) can be seen in Elmasri, R., Navathe, S., Database Systems, 6th Ed.: Chapter 24 pp. 906-920