Querying semi-structured data -- Information integration using logical views -- Methods and problems in data mining -- Conjunctive query containment revisited -- Semantics and containment of queries with internal and external conjunctions -- Efficient complete local tests for conjunctive query constraints with negation -- Selection of views to materialize in a data warehouse -- Total and partial well-founded Datalog coincide -- Fine hierarchies of generic computation -- Local properties of query languages -- Expressiveness and complexity of active databases -- A model theoretic approach to update rule programs -- Abstract interpretation of active rules and its use in termination analysis -- Structural issues in active rule systems -- Discovering all most specific sentences by randomized algorithms extended abstract -- A formal foundation for distributed workflow execution based on state charts -- Incorporating user preferences in multimedia queries -- Queries and computation on the Web -- The complexity of iterated belief revision -- Expressive power of unary counters -- Concurrency control theory for deferred materialized views -- Serializability of nested transactions in multidatabases -- Adding structure to unstructured data -- Correspondence and translation for heterogeneous data -- Type-consistency problems for queries in object-oriented databases -- Object-oriented database evolution -- Performance of nearest neighbor queries in R-trees -- Optimal allocation of two-dimensional data (Extended abstract) -- Efficient indexing for constraint and temporal databases -- On topological elementary equivalence of spatial databases -- Model-theoretic minimal change operators for constraint databases -- Tractable iteration mechanisms for bag languages.

This book constitutes the refereed proceedings of the 6th International Conference on Database Theory, ICDT '97, held in Delphi, Greece, in January 1997. The 29 revised full papers presented in the volume were carefully selected from a total of 118 submissions. Also included are invited papers by Serge Abiteboul and Jeff Ullman as well as a tutorial on data mining by Heikki Mannila. The papers are organized in sections on conjunctive queries in heterogeneous databases, logic and databases, active databases, new applications, concurrency control, unstructured data, object-oriented databases, access methods, and spatial and bulk data.