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X2Q: Your Personal Example-based Graph Explorer

Matteo Lissandrini, Davide Mottin, Themis Palpanas, Yannis Velegrakis


Exploring knowledge graphs can be a daunting task for any user, expert or novice. This is due to the complexity of the schema or because they are unfamiliar with the contents of the data, or even because they do not know precisely what they are looking for. For the same reason there is a significant demand for exploratory methods for this kind of data. We propose X2Q, a system that facilitates the exploration of knowledge graphs with a hands-on approach. X2Q embodies the flexible multi-exemplar query paradigm, in which easy to express examples serve as the basis for formulating sophisticated, and hard to express queries. Our system helps building examples in an interactive fashion, by showing results of the partial exemplar query as well as suggestions for improving the current examples. Then, the user feedback is incorporated in our scores to filter the irrelevant suggestions upfront. X2Q returns answers in real-time on Freebase, one of the largest available knowledge graphs.

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X2Q: Your Personal Example-based Graph Explorer.” Proceedings of the Conference in Very Large Databases (PVLDB), 11 (12): 2018 (pp. 2026-2029).

     author = {Lissandrini, Matteo and Mottin, Davide and Palpanas, Themis and Velegrakis, Yannis},
     title = {X2Q: Your Personal Example-based Graph Explorer},
     booktitle = {Proceedings of the Conference in Very Large Databases (PVLDB), 11 (12) 2018},
     series = {VLDB '18},
     year = {2018},
     location = {Rio, Brazil},
     pages = {2026--2029},
     numpages = {4},
     publisher = {ACM},
     doi = {DOI:},
     address = {New York, NY, USA},
     keywords = {exploration, exemplar queries, labeled graphs, query paradigms},