Tok Wang Ling
National University of Singapore, Singapore

"Data Models Revisited: Improving the Quality of Database Schema Design, Integration and Keyword Search with ORA-Semantics"

Abstract: The concepts of object class, relationship type, and attribute of object class and relationship type, are the three basic concepts in Entity Relationship Model. They are termed ORA-semantics. In this talk, we first recall the limitations of the relational model and XML data model. One serious limitation of these database models is their inability to explicitly represent object classes and relationship types together with their attributes in their schema languages. In fact, these data models have no concepts of ORA-semantics. Without knowing the ORA-semantics in the databases, the quality of some database areas are low. In this talk, we will show that how ORA-semantics can be used to improve the quality significantly in database schema design, data and schema integration, and XML and RDB keyword search. We first present some restrictions in the relational model such as limitations in normalization theory and the use of Universal Relation Assumption in Relational Model. We then briefly describe and compare the 3 common relational database schema design methods, i.e. decomposition method, synthesizing method, and ER Approach. In data and schema integration, entity resolution is widely studied. However, we must also consider relationship resolution which is rarely-mentioned; this is to identify different relationship types between/among same object classes. We also need to differentiate between primary key vs object identifier (OID), local vs global OID, local vs global functional dependency, semantic dependency vs FD/MVD, and schematic discrepancy among schemas. All these concepts are related to ORA-semantics and they have big impact on the quality of the integrated database and schema. We then present same restrictions in the XML data model such as it cannot represent OID of any object class and cannot explicitly capture relationship types, etc. Existing XML keyword search approaches are all LCA-based; they only rely on the structural features but not the hidden ORA-semantics in XML document. Existing RDB keyword search approaches are all based on foreign key-key reference and minimal connected subgraph which contains all the query keywords. We identify some serious problems of the existing XML and RDB keyword search approaches such as interpret the meaning of an answer, meaningless answer, missing answer, schema dependent answer, etc. We exploit the ORA-semantics in XML data and RDB to improve the correctness and completeness of XML and RDB keyword search. We conclude this talk with suggestions on further research topics on schema integration and keyword searches in relational databases and XML databases.

Short Bio: 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 of the Department of Information Systems and Computer Science, and Vice Dean of the School of Computing of the University. He received his PhD and M.Math, both in computer science, from University of Waterloo (Canada) and B.Sc. (1st class Hons) in Mathematics from Nanyang University (Singapore). His current research interests include Database Modeling, Entity-Relationship Approach, Object-Oriented Data Model, Normalization Theory, Semi-Structured Data Model, XML Twig Pattern Query Processing, XML and Relational Database Keyword Query Processing, Temporal Database keyword Query Processing. He serves/served on the steering committees of 5 international conferences, was the SC Chair of both ER and DASFAA, and currently is the SC Chair of BigComp. He served as Conference Co-chair of 12 international conferences, including ER 2004, DASFAA 2005, SIGMOD 2007, VLDB 2010, BigComp 2015, and ER 2018. He served as Program Committee Co-chair of 6 international conferences, including DASFAA 1995, ER 1998, ER 2003, and ER 2011. 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.

Costas Lambrinoudakis
University of Piraeus, Greece

"The General Data Protection Regulation (GDPR) era: Ten steps for compliance of Data Processors and Data Controllers - What about the Users ?"

Abstract: Regulation (EU) 2016/679 of the European Parliament and of the Council (General Data Protection Regulation (GDPR)) aims at harmonizing the legal framework for the Protection of Personal Data in the EU and, at the same time, strengthening the current regime for the protection of personal data for natural persons. GDPR extends the scope of existing legislation to all EU or non-EU controllers who process personal data of citizens of the EU member states and imposes compliance on a sufficiently rigorous legislative framework. The Regulation requires controllers to take all appropriate organizational, procedural and technical measures in order to achieve privacy by default compliance and the satisfaction of all privacy protection principles during the system design (privacy by design). The ultimate goal is to reduce the risks of different probability of occurrence and seriousness for the rights and freedoms of natural persons from processing, taking into account the nature, scope, context and purposes of processing. We will present the ten basic steps that an organization should follow in order to achieve compliance with the requirements of the Regulation.

Short Bio: Dr. Costas Lambrinoudakis holds a B.Sc. (Electrical and Electronic Engineering) from the University of Salford (1985), an M.Sc. (Control Systems) from the University of London (Imperial College -1986), and a Ph.D. (Computer Science) from the University of London (Queen Mary and Westfield College - 1991). Currently he is a Professor at the Department of Digital Systems, University of Piraeus, Greece. From 1998 until 2009 he has held teaching position with the University of the Aegean, Department of Information and Communication Systems Engineering, Greece. For the period 2012-2015 he was a member of the board of the Hellenic Authority for Communication Security and Privacy, while from 2016 he serves on the board of the Hellenic Data Protection Authority. Finally from 2015 he is Head of the Department of Digital Systems and Director of the Systems Security Lab. His current research interests are in the areas of Information and Communication Systems Security and of Privacy Enhancing Technologies. For many years he is working on issues related to the protection of personal data and the compliance of information systems to the National and European Legislation. He is an author of more than 100 scientific publications in refereed international journals, books and conferences, most of them on ICT security and privacy protection issues. He has served as program committee chair of 15 international scientific conferences and as a member on the program and organizing committees in more than 150 others. Also he participates in the editorial board of two international scientific journals and he acts as a reviewer for more than 35 journals. He has been involved in many national and EU funded R&D projects in the area of Information and Communication Systems Security.