VLDB2019 45th International Conference on Very Large Data Bases, Los Angeles, California

Proceedings of the VLDB Endowment

Volume 12, No. 2 – October 2018 Proceedings of the 45th International Conference on Very Large Data Bases, Los Angeles, California

Program Chairs: Lei Chen and Fatma Ö zcan

Associate Editors – Research Track: Azza Abouzied, Selcuk Candan, Surajit Chaudhuri, Amol Desphande, Johann-Christoph Freytag, Rainer Gemulla, Nick Koudas, Georgia Koutrika, Yunyao Li, Alexandra Meliou, Arnab Nandi, M. Tamer Ö zsu, Themis Palpanas, Alkis Polyzotis, Kyuseok Shim, Xiaokui Xiao, Meihui Zhang Proceedings Chairs: Abdul Quamar, Yongxin Tong

PVLDB – Proceedings of the VLDB Endowment Volume 12, No. 2, October 2018. The 45th International Conference on Very Large Data Bases, Los Angeles, California.

Copyright 2018 VLDB Endowment

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc- nd/4.0/. For any use beyond those covered by this license, obtain permission by emailing [email protected].

Volume 12, Number 2, October 2018: VLDB 2019 Pages i – vi and 85 - 182 ISSN 2150-8097

Additional copies only online at: portal.acm.org, arxiv.org/corr, and www.vldb.org

PVLDB Vol. 12 No. 2 i VLDB2019 – Los Angeles, California

TABLE OF CONTENTS

Front Matter Copyright Notice ...... i Table of Contents ...... ii VLDB 2019 Organization and Review Board ...... iii

Research Papers

Exploring Change - A New Dimension of Data Analytics ...... Tobias Bleifuß, Leon Bornemann, Theodore Johnson, Dmitri V. Kalashnikov, Felix Naumann, Divesh Srivastava ...... 85

The Flexible Socio Spatial Group Queries ...... Bishwamittra Ghosh, Mohammed Eunus Ali, Farhana M. Choudhury, Sajid Hasan, Timos Sellis, Jianxin Li ...... 99

The Lernaean Hydra of Data Series Similarity Search: An Experimental Evaluation of the State of the Art ...... Karima Echihabi, Kostas Zoumpatianos, Themis Palpanas, Houda Benbrahim 112

Rafiki: Machine Learning as an Analytics Service System ...... Wei Wang, Sheng Wang, Jinyang Gao, Meihui Zhang, Gang Chen, Teck Khim Ng, Beng Chin Ooi, Jie Shao ...... 128

Automatic Index Selection for Large-Scale Datalog Computation ...... Pavle Subotic, Herbert Jordan, Lijun Chang, Alan Fekete, Bernhard Scholz 141

Start Late or Finish Early: A Distributed Graph Processing System with Redundancy Reduction ...... Shuang Song, Xu Liu, Qinzhe Wu, Andreas Gerstlauer, Tao Li, Lizy K. John 154

Improving Optimistic Concurrency Control Through Transaction Batching and Operation Reordering ...... Bailu Ding, Lucja Kot, Johannes Gehrke 169

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VLDB 2019 ORGANIZATION AND REVIEW BOARD

General Chairs Tutorial Chairs Shahram Ghandeharizadeh, USC Amr El Abbadi, UCSB Xin Luna Dong, Amazon Program Chairs and Editors in Chief of PVLDB 12 Lei Chen, HKUST Industrial Chairs Fatma Özcan, IBM Research – Almaden Beng Chin Ooi, NU Singapore Pat Helland, Salesforce Associate Editors of PVLDB 12 Wolfgang Lehner, Dresden Azza Abouzied, UAE Selcuk Candan, USA Demonstration Chairs Surajit Chaudhuri, USA Alin Deutsch, UCSD Amol Desphande, USA Nesime Tatbul, Intel Labs and MIT Johann-Christoph Freytag, Germany Rainer Gemulla, Germany Panel Chairs Nick Koudas, Canada Sang Kyun Cha, National Seoul University Georgia Koutrika, Greece M. Tamer Özsu, University of Waterloo Yunyao Li, USA Alexandra Meliou, USA Workshop Chairs Arnab Nandi, USA Sharad Mehrotra, UCI M. Tamer Özsu, University of Waterloo Yuanyuan Tian, IBM Research Themis Palpanas, France Alkis Polyzotis, USA PhD Workshop Chairs Kyuseok Shim, South Korea IIlaria Bartolini, University of Bologna Xiaokui Xiao, Singapore Feifei Li, University of Utah Meihui Zhang, China Proceedings Chairs VLDB Endowment Representative Abdul Quamar, IBM Research Michael Carey, UCI Yongxin Tong, Beihang University

Sponsorship Committee Chairs Website Chair Xiaoyong Du, Renmin University Mehran Barahmand, Amazon Volker Markl, TU Berlin Renee Miller, Northeastern PVLDB Managing Editor Divesh Srivastava, AT&T Labs-Research Publicity Committee Chair Sumita Barahmand, Microsoft PVLDB Advisory Committee Jason Yap, Google Peter Boncz, Xin Luna Dong, Juliana Freire, Jayant Haritsa, Wolfgang Lehner, Renée J. Miller, Tova Milo, M. Tamer Özsu

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Research Track Review Board Helen Huang, The University of Queensland Heng Tao Shen, UESTC - China Abdul Quamar, IBM Research - Almaden Hong Cheng, Chinese University of Hong Kong Ada Waichee Fu, Chinese University of Hong Kong Hongzhi YIn, The University of Queensland Ahmet Erdem Sariyuce, University at Buffalo Hua Lu, Aalborg University Alan Fekete, University of Sydney Huiping Cao, NMSU Alkis Simitsis, Microfocus Ilaria Bartolini, University of Bologna Ambuj Singh, UCSB Ilkay Altintas, San Diego Supercomputing Center Andrew Pavlo, CMU Immanuel Trummer, Cornell University Angela Bonifati, University of Lyon - France Ioana Manulescu, French Institute for Research in Arijit Khan, Nanyang Technological University Computer Science and Automation (INRIA) Arnab Bhattacharya, IIT Kanpur Ismail Sengor Altingovde, METU - Turkey Arun Kumar, UC - San Diego James Cheng, Chinese University of Hong Kong Arvind Arasu, Microsoft Jens Dittrich, University of Saarland - Germany Ashraf Aboulnaga, QCRI Jens Teubner, TU Dortmund Ashwin Machanavajjhala, Duke University Jianliang Xu, HKBU Avrilia Floratou, Microsoft Jignesh Patel, University of Wisconsin - Madison Azade Nazi, Microsoft Research Jinyang Gao, National University of Singapore (NUS) - Badrish Chandramouli, Microsoft Research Singapore Barzan Mozafari, University of Michigan Johann Gamper, Free University of Bolzano - Italy Beng Chin OOI, NUS - Singapore Jun Yang, Duke University Berthold Reinwald, IBM Research - Almaden Junjie Yao, East China Normal University Bin Cui, Peiking University - China Kai Zheng, University of Electronic Science and Bobbie Cochrane, IBM Technology of China Bolin Ding, Alibaba Karthik Sankaranarayanan, IBM Research - India Boris Glavic, Illinois Institute of Technology Katja Hose, Aalborg University Bugra Gedik, Bilkent University - Turkey Khuzaima Daudjee, University of Waterloo Byron Choi, Hong Kong Baptist University Kostas Stefanidis, University of Tampere Carlo Curino, Microsoft Research Kostas Zoumpatianos, Harvard University Chee-Yong Chan, National University of Singapore Letizia Tanca, Politecnico di Milano (NUS) - Singapore Lucian Popa, IBM Research - Almaden Chen Li, UC - Irvine Luna Dong, Amazon Chengkai Li, UT Arlington Manos Karpathiotakis, EPFL Chuan Lei, IBM Research - Almaden Maria Luisa Sapino, U. Torino - Italy Cong Yu, Google Mario Nascimento, U. Alberta - Canada Curtis Dyreson, Utah State University Martin Theobald, University of Luxemburg Danica Probic, Oracle Mary Roth, IBM Research - Almaden Daniel Kifer, Penn State University Matthias Boehm, IBM Research - Almaden Davide Mottin, Hasso-Plattner Institute Matthias Renz, George Masion University Demetrios Zeinalipour-Yazti, University of Cyprus Maya Ramanath, IIT Delhi Dimitris Papadias, HKUST Melanie Herschel, University of Stuttgart - Germany Diptikalyan Saha, IBM Research - India Michael Böhlen , University of Zurich Divyakant Agrawal , UCSB Michael Hay, Colgate University Donald Kossmann, Microsoft Research Michael Mathioudakis, University of Helsinki Egemen Tanin, U. Melbourne - Australia Min Li, IBM Research - Almaden Eser Kandogan, IBM Research - Almaden Mirek Riedewald, Northeastern University Essam M. Mansour, QCRI Mirella Moro, Universidade Federal de Minas Gerais Fabio Porto, LNCC - Brazil Mohamed Eltabakh, WPI Fei Chiang, McMaster University Mohamed Mokbel, Qatar Computing Research Feifei Li, University of Utah Institute Florin Rusu, UC Merced Mohamed Sarwat, ASU Floris Geerts, University of Antwerp Murat Kantarcioglu, University of Texas at Dallas George Papadakis, University of Athens Nan Tang, QCRI Goetz Graefe, Google Nicolas Anciaux, French Institute for Research in Guoliang Li, Tsinghua University Computer Science and Automation (INRIA) H. V. Jagadish , University of Michigan Nikolaus Augsten, University of Salzburg Hakan Ferhatosmanoglu, Bilkent University - Turkey Oktie Hassanzadeh, IBM Research - Yorktown Hakan Hacigumus, Google Olga Papaemmanouil , Brandeis University Hanghang Tong, ASU Paolo Papotti, EURECOM - France

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Parth Nagarkar, NMSU Vincent Oria, NJIT Pelin Angin, METU - Turkey Vivek Narasayya, Microsoft Research Philip Bernstein, Microsoft Research Wenjie Zhang, UNSW Philippe Bonnet, ITU - Copenhagen Wook-Shin Han, Postech - Korea Pinar Karagoz, METU - Turkey Xiang Lian, Kent State University Pinar Tozun, ITU - Copenhagen Xiangmin Zhou, RMIT Raymond Ng, UBC Xiaochun Yang, Northeastern University Sai Wu, Zhejiang University Xiaofang Zhou, University of Queensland Sang Kyun Cha, Seoul National University Li Xiong, Emory University Sebastian Breß, DFKI - TU Berlin Xu Chu, Georgia Tech Semih Salihoglu, University of Waterloo Xuemin Lin, University of New Southwales Senjuti Basu Roy, New Jersey Institute of Technology Yael Amsterdamer, Bar-Ilan University Seung-Won Hwang, Yonsei University Yannis Velegrakis, University of Trento - Italy Shaoxu Song, Tsinghua University Yanyan Shen, Shanghai Jiao Tong University Shuo Shang, King Abdullah University of Science and Yi Chen, NJIT Technology Ying Zhang, UTS Spyros Blanas, Ohio State University Yinghui Wu, Washington State University Stefan Mangeold, CWI Amsterdam Yingjun Wu, IBM Research - Almaden Stefano Paraboschi, Università degli Studi di Bergamo Yingxia Shao, Peking University Steffen Zeuch, DFKI - TU Berlin Yongxin Tong, Beihang University Stratis Viglas, University of Edinburgh Yoshiharu Ishikawa, Nagoay University Sudip Roy, Google Ye Yuan, NEU - China Tingjian Ge, University of Massachusetts - Lowell Yuanyuan Tian, IBM Research - Almaden Tyson Condie, Microsoft Yucel Saygin, Sabanci Uni. Turkey Umar Farooq Minhas, Microsoft Research Yunjun Gao, Zhejiang University Vijayshankar Raman, IBM Research - Almaden Zhiguo Gong, University of Macau Viktor Leis, TU Munich

PVLDB Vol. 12 No. 2 v VLDB2019 – Los Angeles, California

LETTER FROM THE PROGRAM CHAIRS

The Proceedings of the VLDB Endowment (PVLDB) provides a high-quality publication service to the data management research community. Each volume offers twelve monthly submission deadlines on the first day of each month and a quick, six week, reviewing cycle. This publication model was pioneered by PVLDB and combines a journal-style reviewing process, which includes a three month revision cycle, with the agility and visibility provided by rapid on-line publication, and presentation at the annual VLDB conference.

PVLDB attracts many submissions spanning diverse data management topics, and the PVLDB reviewing process is implemented by a large team of dedicated researchers. The Review Board of PVLDB Volume 12 consists of 166 expert researchers, and reviewing is coordinated by 17 Associate Editors. Review Board members provide timely (within a 4-week deadline) high-quality reviews, and participate actively in online discussions led by the Associate Editors for each paper.

This is the second issue of the twelfth volume of the PVLDB. There are seven papers accepted in this volume that will be presented in the 45th International Conference on Very Large Data Bases (VLDB 2019), to be held in Los Angeles, California during August 26 to August 30, 2019.

For the second issue of PVLDB Volume 12, the review board has selected contributions proposing advances to topics such as transaction batching, similarity search, social group queries, index selection, and distributed graph processing as well as advanced data management topics such as handling big data changes and using machine learning for providing analytics service. We hope that the selected papers will provide valuable insights to the readers and create impact by inspiring novel systems contributions or follow-up research.

Lei Chen and Fatma Özcan PVLDB Volume 12 Editors in Chief VLDB 2019 Program Committee Chairs

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