TABLE OF CONTENTS

Session 1 Chaired by Avi Silberschatz (University of Texas at Austin)

. Magic Sets and Other Strange Ways To Implement Logic Programs 1 Francois Bancilhon (Microelectronics and Computer Technology Corporation), David Maier (Oregon Graduate Center), Yehoshua Sagiv (Stanford University), and Jeffrey D. Ullman (Stanford University) On the Implementation of a Simple Class of Logic Queries for Databases 16 Domenico Sacca (CRAI, Italy) and Carlo Zaniolo (Microelectronics and Computer Technology Corporation) Convergence of Sideways Query Evaluation 24 Foto Afrati (National Technical University of ), (Stanford University), George Papageorgiou (National Technical University of Athens), Athena Roussou (National Technical University of Athens), Yehoshua Sagiv (Stanford University), and Jeffrey D. Ullman (Stanford University)

Session 2 Chaired by Hector Garcia-Molina (Princeton University)

A Theoretical Foundation of Multi-Level Concurrency Control 31 Gerhard Weikum (Technical University Darmstadt) Deleting Completed Transactions 43 Thanasis Hadzilacos (National Technical University of Athens) and (AT&T Bell Labs) Safety of Non-well-locked Transaction Systems 47 Jianwen Su (Fudan University, Shanghi and University of Lowell)

Session 3 Chaired by Meral Ozsoyoglu (Case Western Reserve University)

A Calculus for Complex Objects 53 Francois Bancilhon and Setrag Khoshafian (Microelectronics and Computer Technology Corporation) Some Classes of Multilevel Relational Structures 60 Dirk Van Gucht (Indiana University at Bloomington) and Patrick C. Fischer (Vanderbilt University) Weak Temporal Relations 70

Shashi K. Gadia (Texas Tech University)

Session 4 Chaired by Per-Ake Larson (University of Waterloo)

Rearranging Data to Maximize the Efficiency of Compression 78 Frank Olken and Doron Rotem (Lawrence Berkeley Laboratory) Order Preserving Linear Hashing Using Dynamic Key Statistics 91 John T. Robinson (IBM Thomas J. Watson Research Center) Balanced Multidimensional Extendible Hash Tree 100 Ekow J. Otoo (Carleton University) Session 5 Chaired by (IBM Almaden Research Center)

Negation as Failure for First-Order Queries 114 Shamim A. Naqvi (AT&T Bell Labs) Positivism vs. Minimalism in Deductive Databases 123 Nicole Bidoit (INRIA) and Richard Hull (University of Southern California) The Extended Closed World Assumption and Its Relationship to Parallel Circumscription 133 M. Gelfond, H. Przymusinska, and T. Przymusinski (University of Texas at El Paso)

Session 6 Chaired by Alberto Mendelzon (University of Toronto)

On the Properties and Characterization of Connection-trap-free Schemes 140 Edward P. F. Chan (University of Alberta) and Paolo Atzeni (IASI-CNR) One Flavor Assumption and Gamma-acyclicity for UniversabRelation Views 148 J. Biskup (Universitat Dortmund), H. H. Bruggemann (Universitat Dortmund), L. Schnetgoke (Universitat Dortmund), and M. Kramer (FernUniversitat Hagen) The Equivalence of Solving Queries and Producing Tree Projections 160 Yehoshua Sagiv (Stanford University) and Oded Shmueli (Technion-Israel Institute of Technology)

Session 7 Chaired by Ed Sciore (Boston University)

On Finite FD-Acyclicity 173 Yehoshua Sagiv (Stanford University) and Oded Shmueli (Technion-Israel Institute of Technology) Unifying Functional and Multivalued Dependencies for Relational Database Design 183 Meral Ozsoyoglu and Li-Yan Yuan (Case Western Reserve University) Alpha-acyclic Decompositions of Relational Database Schemes 191

Detlev Ruland and Dietmar Seipel (University at Wuerzburg)

Session 8 Chaired by Ronald Fagin (IBM Research Lab)

Constant Time Maintenance or the Triumph of the fd 202 Marc Graham and Ke Wang (Georgia Institute of Technology) Test Data for Relational Queries 217 Heikki Mannila (University of Helsinki) and Kari-Jouko Raiha (University of Tampere) A Model-Theoretic Approach to Updating Logical Databases 224 Marianne Winslett Wilkins (Stanford University) Session 9 Chaired by Paris Kanellakis ()

Deciding Properties of Transactional Schemas 235 (INRIA) and Victor Vianu (University of California, San Diego) Availability in Partitioned Replicated Databases 240

Amr El Abbadi and Sam Toueg (Cornell University)

Session 10 Chaired by Francois Bancilhon (Microelectronics and Computer Technology Corporation)

On the Integrity of Databases with Incomplete Information 252 Moshe Vardi (IBM Almaden Research Center) Data Independent Recursion in Deductive Databases 267 Jeff Naughton (Stanford University) Parallel Evaluation of Recursive Rule Queries 280 S. Cosmadakis (IBM Thomas J. Watson Research Center) and Paris Kanellakis (Brown University)