Progressive Evaluation of XML Queries for Online Aggregation and Progress Indicator

With the rapid proliferation of XML data, large-scale online applications are emerging. In this research, we aim to enhance the XML query processors with the ability to process queries progressively and report partial results and query progress continually. The methodology lays its foundation on sampling. We shed light on how effective samples can be drawn from semi-structured XML data, as opposed to flat-table relational data. Several innovative sampling schemes on XML data are designed. The proposed methodology advances XML query processing to the next level - being more flexible, responsive, user-informed, and user-controllable, to meet emerging needs and future challenges.