Query-based Why-not Explanations for Nested Data


Ralf Diestelkämper, IPVS–University of Stuttgart; Boris Glavic, Illinois Institute of Technology; Melanie Herschel, IPVS–University of Stuttgart; Seokki Lee, Illinois Institute of Technology


We present the first query-based approach for explaining missing answers to queries over nested relational data which is a common data format used by big data systems such as Apache Spark. Our main contributions are a novel way to define query-based why-not provenance based on repairs to queries and presenting an implementation and preliminary experiments for answering such queries in Spark.

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@inproceedings {235858,
author = {Ralf Diestelk{\"a}mper and Boris Glavic and Melanie Herschel and Seokki Lee},
title = {Query-based Why-not Explanations for Nested Data},
booktitle = {11th International Workshop on Theory and Practice of Provenance (TaPP 2019)},
year = {2019},
address = {Philadelphia, PA},
url = {https://www.usenix.org/conference/tapp2019/presentation/diestelkamper},
publisher = {USENIX Association},
month = jun