Parsing skyline queries

The existing works only consider how to efficiently process skyline computation for a single table. That is, they assume the issued skyline queries do not involve any traditional relational operator. Clearly, in most real applications, the query efficiency is extremely low because of this unreasonable assumption. Motivated by these facts, in this paper, we regard skyline computation as a special relational operator and study the equivalence transformation rules of implementation order between it and traditional relational operators. Then based on these equivalence transformation rules, we can efficiently improve the query performance. Moreover, we present sufficient theoretical proofs to demonstrate the correctness of the proposed equivalence transformation rules. The extensive experiments also show that the after-transforming solutions markedly outperforms the before-transforming counterparts.EI081639-16453