The multi-criteria decision making, which is possible with the advent of skyline queries, has been applied in many areas. Though most of the existing research is concerned with only a single relation, several real world applications require finding the skyline set of records over multiple relations. Consequently, the join operation over skylines where the preferences are local to each relation, has been proposed. In many of those cases, however, the join often involves performing aggregate operations among some of the attributes from the different relations. In this paper, we introduce such queries as “aggregate skyline join *
There are various algorithms for joining such as nested-loop join, indexed nested-loop join, merge-join and hash-join @cite_9 . Nested-loop joins can be used regardless of the join condition. The other join techniques are more efficient, but can handle only simple join conditions, such as natural joins or equi-joins. Any of these join algorithms that is applicable for the given query can be used with ASJQ algorithms.
@cite_9
1512840853
From the Publisher: This acclaimed revision of a classic database systems text offers a complete background in the basics of database design, languages, and system implementation. It provides the latest information combined with real-world examples to help readers master concepts. All concepts are presented in a technically complete yet easy-to-understand style with notations kept to a minimum. A running example of a bank enterprise illustrates concepts at work. To further optimize comprehension, figures and examples, rather than proofs, portray concepts and anticipate results.