Group-by skyline query processing in relational engines

13 years 11 months ago

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The skyline operator was ﬁrst proposed in 2001 for retrieving interesting tuples from a dataset. Since then, 100+ skyline-related papers have been published; however, we discovered that one of the most intuitive and practical type of skyline queries, namely, groupby skyline queries remains unaddressed. Group-by skyline queries ﬁnd the skyline for each group of tuples. In this paper, we present a comprehensive study on processing group-by skyline queries in the context of relational engines. Speciﬁcally, we examine the composition of a query plan for a group-by skyline query and develop the missing cost model for the BBS algorithm. Experimental results show that our techniques are able to devise the best query plans for a variety of group-by skyline queries. Our focus is on algorithms that can be directly implemented in today’s commercial database systems without the addition of new access methods (which would require addressing the associated challenges of maintenance with upd...

Ming-Hay Luk, Man Lung Yiu, Eric Lo

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