In the database research field the management of temporal and spatial information is crucial. Many information may be temporally and spatially qualified, i.e., data may be associated to temporal and spatial locations. In the management of qualified data, the notion of "granularity" plays an important role; it allows one to reason about temporal and spatial… (More)
Issues related to fuzzy data have been investigated in the classical database research field, and in the last years are becoming interesting topics also in the XML data context. In this work we propose a general XML schema definition for representing fuzzy information.
Spatial granularities allow one to qualify classical data adding them space locations. In order to compare data qualified with different granularities and to associate data to different granularities (e.g., in analysis similar to drill-down and roll-up operations), it is necessary to know how the involved granularities are related. However, the explicit… (More)
In many different application fields the amount and importance of spatio-temporal data (i.e., temporally and/or spatially qualified data) is increasing in last years and users need new solutions for their management. In this paper we propose a spatio-temporal query language, called ST4SQL. The proposed language extends the well-known SQL syntax and the… (More)
Ουτος ὑμων, ω ανθρωποι, σοφώτατός ἐστιν, οστις ωσπερ Σωκράτης γνωκεν οτι οὐδενὸς αξιός ἐστι τῃ ἀληθείᾳ πρὸς σοφίαν. He, O men, is the wisest, who, like Socrates, knows that his wisdom is in truth worth nothing. Summary In several research fields, temporal, spatial, and spatio-temporal data have to be managed and queried with several purposes. These data are… (More)
Temporal, spatial, and spatio-temporal granularities allow one to qualify classical data locating them in time and space. In order to compare data qualified with different granularities and associate data to different granularities, it is necessary to know how the involved granularities are related. However, the explicit calculation of these relationships… (More)
The notion of granularity is used in several areas of computing. In temporal databases, granularity relates to the fact that the time frame associated to an event of interest (e.g., an accident) can be envisaged at several levels of detail (e.g., hour, day, month, etc.). Similarly, granularity in data warehousing is the level of detail at which facts (e.g.,… (More)