Getting the best from skylines and top-k queries

TL;DR

This paper explores combining skyline and top-k query techniques to leverage their respective strengths, addressing limitations in controlling output size and specifying attribute trade-offs.

Contribution

It introduces a new flexible dominance relation that integrates skyline and ranking query advantages, providing a more adaptable query approach.

Findings

The proposed method effectively balances skyline simplicity and ranking control.

Experimental results show improved flexibility in output cardinality.

The approach enhances user control over query results.

Abstract

Top-k and skylines are two important techniques that can be used to extract the best objects from a set. Both the approaches have well-known pros and cons: a quite big limitation of skyline queries is the impossibility to control the cardinality of the output and the difficulty in specifying a trade-off among attributes, whereas the ranking queries allow so. On the other hand, the usage of ranking implies that ranking functions need to be specified by users and renouncing the simplicity of skylines. Flexible/ restricted skylines present a new approach to tackle this problem, combining the best characteristics of both techniques making use of a new flexible relation of dominance.