skyline query經常運用於多準則決策系統或支援決策分析系統中，可以根據使用者的偏好篩選出符合需求的最佳結果集合。隨著資訊量增加，資料來源不同，表格之間存在共有的屬性，可以根據共有的屬性進行join運算。若是將資料進行join再查找skyline相當浪費資源，因為join會使得資料分量和資料量急遽上升，且產生眾多非skyline資料，造成篩選運算成本變多，影響整體執行時間。本論文提出兩階段的篩選機制，配合樹狀資料結構輔助可以有效篩選資料並且減少比較次數。實驗結果與常見的演算法比較，本研究提出的方法能快速有效的篩選資料。

Skyline query is often used in multi-criteria decision-making systems or in decision support systems. It can be used to sort out the best result in accordance with the user's preferences. As the amount of information increases, the data may come from different sources and different data tables may have common attributes that can be used to carry out join operation. It is a waste of resources to join the data first and then search for the skyline, because join operation will increase substantially the data component as well as the data volume and generate a lot of non-skyline data, resulting in more screening computation costs and affecting the overall execution time. This paper proposes a two-stage screening mechanism, which can effectively sort data and reduce the number of comparisons through the support of a tree data structure. The experimental results show that the method proposed in this study can sort the data more quickly and effectively then other popular algorithms.

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