Ontology-Based Database Approach for Handling Preferences - Data Warehousing Design and Advanced Engineering Applications - page 267

Figure 8. Numeric and interval preferences instantiation

to the interval [45, 60] and the expensive quality
any price between 90 and 100.

UPDATE #Property_Or_Class set
#Pref_link=ARRAY ['cheap', 'expen-
sive'] where #name='price';
UPDATE #Property_Or_Class set
#Pref_link=ARRAY ['standard'] where
#name='starRate';

INSERT INTO Interval_
Preference(#label, #min_value,
#max_value)
VALUES('cheap',45, 60);
INSERT INTO Interval_
Preference(#label, #min_value,
#max_value)
VALUES('expensive',90, 100);

When the preferences are linked to the ontology
concepts, the database can be queried.

Querying OntoDB with Preferences

Once the three previous steps are realised, it be-
comes possible to query the implemented model.
We give below two examples of queries with an
asserted quality on the data thanks to the PRE-
FERRING clause.

Attaching Preferences to the
Ontology of the Tourism Domain

When the preferences and the ontology have been
defined, the next step is to link ontology entities
to the preferences that are expressed on these enti-
ties. In our case, a preference is attached to the
price and to the star rating property. We update the
Property_Or_Class entity accordingly. The first
instruction below link the property price to the
interval preferences defined previously.

1. A query that gives only the 3 stars hotels is

written as follows.