The HyperView Approach to the Integration of Semistructured Data

Title page, contents 1 Introduction 1.1 Integration of semistructured information sources Virtual Web Sites 1.2 The HyperView approach 1.2.1 Data Model and View Mechanism 1.2.2 Architecture 1.2.3 Application of the HyperView Technology 1.3 Related Work (Overview) 1.4 Overview 2 HyperView by Example: Wrapping Publisher Web Sites 2.1 Digital Libraries of Electronic Journals 2.1.1 The DARWIN project 2.1.2 Use cases 2.2 Modeling publisher Web Sites 2.2.1 Generic approach 2.2.2 Graph Schemata 2.2.3 The HyperView Database Schema 2.2.4 ACR Schemata of Example Web Sources 2.2.5 Representing HTML Pages as HTML graphs 2.3 Building Views on publisher Web Sites 2.3.1 Queries and Rules 2.3.2 Defining a View over the HTML Graphs 2.3.3 Defining a View over the ACR Graphs 2.3.4 Querying the HyperView system 2.4 The Architecture of DARWIN 2.5 Summary 3 Formal Framework 3.1 Clustered Graph Data Model (CGDM) 3.1.1 Motivation 3.1.2 Basic definitions 3.1.3 Schemata and instances 3.2 Rules 3.2.1 Rule application 3.3 Queries and Oracles 3.3.1 Applying a rule to a virtual data graph 3.3.2 Hyperviews 3.3.3 Using a rule to answer a subquery 3.3.4 Chaining rules to answer a query 3.4 Reuse of existing subgraphs 3.5 Bibliography on Graph-Transformation 3.6 Summary 4 The HyperView System 4.1 Encoding of Graphs 4.1.1 Plain Graphs 4.1.2 Clustered Graphs 4.1.3 Type checking 4.2 Encoding of Queries 4.3 Encoding of Rules 4.4 Rule Activation 4.5 Query execution 4.6 Complexity and Performance 4.7 Metadata management 4.7.1 Schema clusters 4.7.2 The `meta` cluster 4.7.3 WWW meta data 4.8 The HyperView System prototype 4.9 Summary 5 The HVQL Query Language 5.1 Introduction 5.2 Basic Notations 5.3 Graph Patterns 5.4 Graph Literals 5.5 Queries 5.5.1 Syntax 5.5.2 Semantics 5.5.3 Implementation 5.6 Rules 5.6.1 Syntax 5.6.2 Semantics 5.6.3 Implementation 5.6.4 Example 5.7 Meta Edges 5.8 HTML Edges 5.9 Embedding of HVQL in the HyperView System 5.10 Summary 6 Support for Web Interfaces 6.1 Introduction 6.2 Architecture of the HyperView Web server 6.3 Conceptual model of the virtual HyperView Web site 6.4 HTML Code Generation 6.4.1 Phase 1: Preparation 6.4.2 Phase 2: Generation of a HTML skeleton 6.4.3 Phase 3: HTML dump and generation of variable HTML code 6.4.4 HVQL notation for HTML rules 6.5 The HyperView Browser 6.5.1 Customization 6.6 Summary 7 Case Study: Town Information 7.1 Introduction 7.2 Scenario 7.2.1 Use Case 7.3 Developing a cultural event calendar 7.3.1 Conceptual schema 7.3.2 Wrapping town information sites 7.4 The cultural calendar Web site 7.5 Summary 8 The HyperView Methodology 8.1 User roles 8.2 Content Specification 8.3 The Design Space of HyperView 8.4 Schema development 8.4.1 HTML layer 8.4.2 ACR layer 8.4.3 Database layer 8.4.4 UI layer 8.5 View development 8.5.1 Implementing HTML views 8.5.2 ACR Views 8.5.3 DB Views 8.6 Maintenance 8.6.1 Robustness 8.6.2 Error detection 8.6.3 Adaption 8.7 Summary 9 Discussion and Outlook 9.1 Related Work 9.1.1 Data models and schemata for semistructured data 9.1.2 Data Extraction from Semistructured Documents 9.1.3 Querying the Web 9.1.4 Integration of Heterogeneous Data Sources 9.1. 5 Related applications of Graph- Transformation techniques 9.1. 6 Comparison with HyperView 9.2 Future Applications: XML & RDF 9.2.1 XML 9.2.2 XML Parsing 9.2.3 XML DTD s and schemata 9.2.4 XPointer and XQL 9.2.5 Extensible Stylesheet Language 9.2. 6 Channel Definition Format 9.2. 7 Resource Description Framework (RDF) 9.2. 8 RDF Schemata 9.2. 9 Summary 9.3 Open Issues 9.3.1 Theoretical Issues 9.3.2 Integration Issues 9.3.3 Implementation and Performance Issues 9.3.4 Interface Issues 9.4 Contributions and Outlook 9.5 Acknowledgments Bibliography Table of Mathematical Symbols Zusammenfassung der Ergebnisse Lebenslauf Verwendete Hilfsmittel