LING Tok Wang

Ph.D. (Computer Science, University of Waterloo, Canada, 1978)
M.Math. (Computer Science, University of Waterloo, Canada, 1973)
B.Sc. (Mathematics, 1st Class Honours, Nanyang University, Singapore, 1971)
B.Sc. (Mathematics, Nanyang University, Singapore, 1970)
651 62734

Research Areas

  • Database

Research Interests

  • Data Modeling
  • Normalization Theory and Database Design
  • Keyword Query Processing on Relational/ XML Databases/ Temporal Databases using ORA-Semantics
  • Entity-Relationship Approach
  • Object-Oriented Data Model
  • Normalization Theory
  • Logic and Database
  • Integrity Constraint Checking
  • Semi-Structured Data Model
  • XML Twig Pattern Query Processing
  • ORA-Semantics Based XML
  • Relational Database Keyword Query Processing
  • Data Warehouse


Dr. Tok Wang Ling is a professor in Computer Science Department at the National University of Singapore. He was Head of IT Division, Deputy Head and acting head of the Department of Information Systems and Computer Science, and Vice Dean of the School of Computing of the University. Before joining the University as a lecturer in 1979, he was a scientific staff at Bell Northern Research, Ottawa, Canada. He serves/served on the program committee of more than 160 international database conferences including VLDB, CIKM, EDBT, ER, DASFAA, DOOD, DEXA, CoopIS, DOLAP, DaWaK, ADC, BigComp, etc. He organized and served as a program committee co-chair of 6 international database conferences, namely DASFAA 1995, DOOD 1995, ER 1998, WISE 2002, ER 2003, and ER 2011. He organized and served as a conference co-chair of several conferences and workshops, namely HSI 2001, 2003, and 2005, WAIM 2004, ER 2004, DASFAA 2005, DASFAA 2006 (Honorary Chair), SIGMOD 2007, VLDB 2010, DASFAA 2014 (Honorary Chair), BigComp 2015. He serves/served on the steering committees of 5 international conferences, namely ER, DASFAA, DOOD, HSI, and BigComp. He was the steering committee chair of both ER and DASFAA. He is currently the steering committee chair of BigComp. He is an editorial board member of the several international journals, namely Data & Knowledge Engineering, Journal of Database Management, Journal of Data Semantics, Journal of Information and Data Management, Journal of Computing Science and Engineering (International Advisory Board member). He is an ER Fellow, an ACM Distinguished Scientist, IEEE Senior Life Member, and Fellow of Singapore Computer Society. He received the ACM Recognition of Service Award in 2007, the DASFAA Outstanding Contributions Award in 2010, and the Peter P. Chen Award in 2011.

Current Projects

  • Temporal Keyword Search in Medical Record Databases

Selected Publications

  • Tok Wang Ling, Frank Wm. Tompa, Tiko Kameda:
    An Improved Third Normal Form for Relational Databases. ACM Trans. Database Syst. 6(2): 329-346 (1981).

  • Tok Wang Ling:
    A Normal Form for Entity-Relationship Diagrams. ER 1985: 24-35.

  • Tok Wang Ling, Ling-Ling Yan:
    NF-NR: A practical normal form for nested relations. Journal of Systems Integration 4(4): 309-340 (1994).

  • Xiaoying Wu, Tok Wang Ling, Mong-Li Lee, Gillian Dobbie:
    Designing Semistructured Databases Using ORA-SS Model. WISE (1) 2001: 171-182.

  • Mengchi Liu, Gillian Dobbie, Tok Wang Ling:
    A logical foundation for deductive object-oriented databases. ACM Trans. Database Syst. 27(1): 117-151 (2002).

  • Jiaheng Lu, Tok Wang Ling, Chee Yong Chan, Ting Chen:
    From Region Encoding To Extended Dewey: On Efficient Processing of XML Twig Pattern Matching. VLDB 2005: 193-204.

  • Zhifeng Bao, Tok Wang Ling, Bo Chen, Jiaheng Lu:
    Effective XML Keyword Search with Relevance Oriented Ranking. ICDE 2009: 517-528.

  • Thuy Ngoc Le, Huayu Wu, Tok Wang Ling, Luochen Li, Jiaheng Lu:
    From Structure-Based to Semantics-Based: Towards Effective XML Keyword Search. ER 2013: 356-371.

  • Zhong Zeng, Zhifeng Bao, Mong-Li Lee, Tok Wang Ling:
    A Semantic Approach to Keyword Search over Relational Databases. ER 2013: 241-254.

  • Thuy Ngoc Le, Zhifeng Bao, Tok Wang Ling:
    Schema-Independence in XML Keyword Search. ER 2014: 71-85.

Awards & Honours

  • He received the ACM Recognition of Service Award in 2007, the DASFAA Outstanding Contributions Award in 2010, and the Peter P. Chen Award in 2011.

Teaching (2020/2021)