Invited Paper -- XML Databases and Beyond-Plenty of Architectural Challenges Ahead -- Regular Papers Database Theory -- Usable Recursive Queries -- Relation-Collapse: An Optimisation Technique for the Similarity Algebra -- On Modal Deductive Databases -- Declarative Data Fusion – Syntax, Semantics, and Implementation -- Non-destructive Integration of Form-Based Views -- Database Modelling and Physical Database Design -- A Multi-version Data Model and Semantic-Based Transaction Processing Protocol -- Managing Schema Versions in Object-Oriented Databases -- Efficient Integrity Checking for Databases with Recursive Views -- A Formal Model for the Problem of View Selection for Aggregate Queries -- Efficient Main-Memory Algorithms for Set Containment Join Using Inverted Lists -- Query Processing -- VA-Files vs. R*-Trees in Distance Join Queries -- The Expressivity of Constraint Query Languages with Boolean Algebra Linear Cardinality Constraints -- Heterogeneous Databases and Interoperability -- Extensible Canonical Process Model Synthesis Applying Formal Interpretation -- Location Awareness of Information Agents -- XML and Databases -- Algebraic Semantics of XML Schema -- Efficient XPath Evaluation -- A Prototype for Translating XQuery Expressions into XSLT Stylesheets -- Combining Tree Structure Indexes with Structural Indexes in Query Evaluation on XML Data -- A DataGuide-Based Concurrency Control Protocol for Cooperation on XML Data -- Data Mining and Knowledge Discovery -- Mining Fuzzy Classification Rules Using an Artificial Immune System with Boosting -- Continuous Trend-Based Classification of Streaming Time Series -- Information Systems and Software Engineering -- Conceptual Content Management for Software Engineering Processes -- Using Step-Wise Refinement to Build a Flexible Lightweight Storage Manager -- BiChord: An Improved Approach for Lookup Routing in Chord -- Information Systems Development -- On Business Rules Automation: The BR-Centric IS Development Framework -- CFP Taxonomy of the Approaches for Dynamic Web Content Acceleration -- Long-Term Temporal Data Representation of Personal Health Data.The 9th East-European Conference on Advances in Databases and Information Systems was held on September 12–15, 2005, in Tallinn, Estonia. It was organized in a cooperation between the Institute of Cybernetics at Tallinn University of Technology, the Department of Computer Engineering of Tallinn University of Technology, and the Moscow chapter of ACM SIGMOD. The main objective of the ADBIS series of conferences is to provide a - rum for the disseminationof excellent researchaccomplishmentsand to promote interaction and collaboration between the Database and Information Systems research communities from Central and East European countries and the rest of the world. The ADBIS conferences provide an international platform for the presentationofresearchondatabasetheory,thedevelopmentofadvancedDBMS technologies, and their advanced applications in particular in information s- tems. The 2005 conference continued the ADBIS conferences held in St. Pete- burg (1997), Poznan (1998), Maribor (1999), Prague (2000), Vilnius (2001), Bratislava (2002), Dresden (2003), and Budapest (2004). The conference c- sisted of regular sessions with technical contributions reviewed and selected by an international Program Committee, as well as of invited talks and tutorials given by leading scientists. For the ?rst time the ADBIS conferences had a satellite event, a workshop on data mining and knowledge discovery. The ADMKD 2005 workshop,with its own international ProgramCommittee as well as proceedings, servedas a forum toencourageresearchersandpractitionerstodiscussandinvestigatedatamining research and implementation issues, and to share experience in developing and deploying data mining systems.