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arXiv · 1902.04938

Snapshot Semantics for Temporal Multiset Relations (Extended Version)

Anton Dignös·Boris Glavic·Xing Niu·Michael Böhlen·Johann Gamper
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Abstract

Snapshot semantics is widely used for evaluating queries over temporal data: temporal relations are seen as sequences of snapshot relations, and queries are evaluated at each snapshot. In this work, we demonstrate that current approaches for snapshot semantics over interval-timestamped multiset relations are subject to two bugs regarding snapshot aggregation and bag difference. We introduce a novel temporal data model based on K-relations that overcomes these bugs and prove it to correctly encode snapshot semantics. Furthermore, we present an efficient implementation of our model as a database middleware and demonstrate experimentally that our approach is competitive with native implementations and significantly outperforms such implementations on queries that involve aggregation.

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Anton Dignös, Boris Glavic, Xing Niu, Michael Böhlen, Johann Gamper. 2019-02-13. Snapshot Semantics for Temporal Multiset Relations (Extended Version). https://arxiv.org/abs/1902.04938

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