On Computing Temporal Aggregates over Null Time Intervals
نویسنده
چکیده
In a temporal database, each data tuple is accompanied by a time interval during which its attribute values are valid. In this paper, we consider the null time intervals, that is, time intervals not intersected by any time intervals in the temporal database. We deal with the problem of computing temporal aggregates over null time intervals with length constraints. By interval folding, we transform the problem into aggregates over stabbing groups, maximal stabbing interval sets. We describe the detailed algorithms and report the experimental results.
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