The following papers (listed in a random order) have been accepted at the 6th International Conference on Database Theory (ICDT '97), Delphi, Greece - January 8-10, 1997. ------------------------------------------------------------------- Semantics and Containment with Internal and External Conjunctions --- G. Grahne, N. Spyratos, D. Stamate Total and Partial Well-Founded Datalog Coincide --- J. Flum, M. Kubierschky, B. Ludascher Correspondence and Translation for Heterogeneous Data --- S. Abiteboul, S. Cluet, T. Milo Discovering all most specific sentences by randomized algorithms --- D. Gunopoulos, H. Mannila, S. Saluja A Model Theoretic Approach to Update Rule Programs --- N. Bidoit, S. Maabout Fine Hierarchies of Generic Computation --- J. Tyszkiewicz The Complexity of Iterated Belief Revision --- P. Liberatore A Formal Foundation for Distributed Workflow Execution Based on State Charts --- D. Wodtke, G. Weikum Performance of Nearest Neighbor Queries in R-trees --- A. Papadopoulos, Y. Manolopoulos Expressiveness and Complexity of Active Databases --- P.Picouet, V.Vianu Adding Structure to Unstructured Data --- P.Buneman, S.Davidson, M. Fernandez, D.Suciu Type consistency problems for queries in object-oriented databases --- Y. Ishihara, H. Seki, M. Ito Optimal allocation of two-dimensional data --- K. Abdel-Ghaffar, A. El Abbadi On topological elementary equivalence of spatial databases --- B. Kuijpers, J. Paredaens, J. Van den Bussche Object-oriented database evolution --- J.-B. Lagorce, A. Stockus, E. Waller Local properties of query languages --- G. Dong , L. Libkin, L. Wong Concurrency control theory for deferred materialized views --- A. Kawaguchi , D. Lieuwen, I. Mumick, D. Quass, K. Ross Efficient indexing for constraint and temporal databases --- S. Ramaswamy Serializability of nested transactions in multidatabases --- U. Halici, B. Arpinar, A. Dogac Efficient complete tests for conjunctive query constraints with negation --- N. Huyn Incorporating user preferences in multimedia queries --- R. Fagin, E.L. Wimmers Tractable iteration mechanisms for bag languages --- L. Colby, L. Libkin, Dynamic constraint databases for spatial data --- P.Z. Revesz Queries and computation on the web --- S. Abiteboul, V. Vianu Selection of views to materialize in a data warehouse --- H. Gupta Conjunctive query containment revisited --- C. Chekuri, A. Rajaraman Abstract interpretation of active rules and its use in termination analysis --- J. Bailey, L. Crnogorac, K. Ramamohanarao , H. Sondergaard Structural issues in active rule systems --- J. Bailey, G. Dong, K. Ramamohanarao Expressive Power of Unary Counters --- M. Benedikt, H.J. Keisler