Abstract : In this paper, we propose a personalized approach for flexible querying of information systems. This approach consists in the combination of the reasoning capabilities of the fuzzy DLR-Lite ontology and the expressivity of the SQLf language. The interpretation of the gradual inclusion (subsumption) axioms of the ontology is based on the G¨odel fuzzy implication. Its generalization to a tree of inclusions is also proposed. This tree and its property of propagation of degrees are the basic theoretical elements of our application, which consists in querying of a multimodal transport information system which is embedded in a mobile terminal characterized by limited storage and processing capabilities.