Query processing in a system for distributed databases (SDD-1)
ACM Transactions on Database Systems (TODS)
Implementing a relational database by means of specialzed hardware
ACM Transactions on Database Systems (TODS)
ACM Transactions on Database Systems (TODS)
Normalization and hierarchical dependencies in the relational data model
ACM Transactions on Database Systems (TODS)
Decomposition—a strategy for query processing
ACM Transactions on Database Systems (TODS)
Performance evaluation of a relational associative processor
ACM Transactions on Database Systems (TODS)
Multivalued dependencies and a new normal form for relational databases
ACM Transactions on Database Systems (TODS)
On the menbership problem for functional and multivalued dependencies in relational databases
ACM Transactions on Database Systems (TODS)
Using Semi-Joins to Solve Relational Queries
Journal of the ACM (JACM)
Distributed query processing in a relational data base system
SIGMOD '78 Proceedings of the 1978 ACM SIGMOD international conference on management of data
A complete axiomatization for functional and multivalued dependencies in database relations
SIGMOD '77 Proceedings of the 1977 ACM SIGMOD international conference on Management of data
Access path selection in a relational database management system
SIGMOD '79 Proceedings of the 1979 ACM SIGMOD international conference on Management of data
A methodology for interpreting tree queries into optimal semi-join expressions
SIGMOD '80 Proceedings of the 1980 ACM SIGMOD international conference on Management of data
Optimal semijoin schedules for query processing in local distributed database systems
SIGMOD '81 Proceedings of the 1981 ACM SIGMOD international conference on Management of data
PODS '82 Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems
Connections in acyclic hypergraphs: extended abstract
PODS '82 Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems
Properties of acyclic database schemes
STOC '81 Proceedings of the thirteenth annual ACM symposium on Theory of computing
Resolving the query inference problem using Steiner trees
ACM Transactions on Database Systems (TODS)
A framework for choosing a database query language
ACM Computing Surveys (CSUR)
A state transition model for distributed query processing
ACM Transactions on Database Systems (TODS)
The equivalence of solving queries and producing tree projections (extended abstract)
PODS '86 Proceedings of the fifth ACM SIGACT-SIGMOD symposium on Principles of database systems
Sagiv,Y-On finite FD-acyclicity
PODS '86 Proceedings of the fifth ACM SIGACT-SIGMOD symposium on Principles of database systems
PODS '89 Proceedings of the eighth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Optimizing equijoin queries in distributed databases where relations are hash partitioned
ACM Transactions on Database Systems (TODS)
Solving queries by tree projections
ACM Transactions on Database Systems (TODS)
On the optimality of strategies for multiple join
Journal of the ACM (JACM)
Perspectives on database theory
ACM SIGACT News
On the decidability and axiomatization of query finiteness in deductive databases
Journal of the ACM (JACM)
Quasilinear algorithms for processing relational calculus expressions (preliminary report)
PODS '90 Proceedings of the ninth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Hypertree decompositions and tractable queries
PODS '99 Proceedings of the eighteenth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
An axiomatic approach to deciding query safety in deductive databases
Proceedings of the seventh ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Query processing in a system for distributed databases (SDD-1)
ACM Transactions on Database Systems (TODS)
On the Desirability of Acyclic Database Schemes
Journal of the ACM (JACM)
Degrees of acyclicity for hypergraphs and relational database schemes
Journal of the ACM (JACM)
Syntactic Characterization of Tree Database Schemas
Journal of the ACM (JACM)
Query Optimization in Database Systems
ACM Computing Surveys (CSUR)
The complexity of acyclic conjunctive queries
Journal of the ACM (JACM)
Functional dependencies on cyclic database schemes
SIGMOD '83 Proceedings of the 1983 ACM SIGMOD international conference on Management of data
GYO reductions, canonical connections, tree and cyclic schemas and tree projections
PODS '83 Proceedings of the 2nd ACM SIGACT-SIGMOD symposium on Principles of database systems
SIGMOD '84 Proceedings of the 1984 ACM SIGMOD international conference on Management of data
On the Complexity of Distributed Query Optimization
IEEE Transactions on Knowledge and Data Engineering
Weighted hypertree decompositions and optimal query plans
PODS '04 Proceedings of the twenty-third ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
Query answering exploiting structural properties
ACM SIGMOD Record
Improvement Algorithms for Semijoin Query Processing Programs in Distributed Database Systems
IEEE Transactions on Computers
Uniform Constraint Satisfaction Problems and Database Theory
Complexity of Constraints
A self-policing policy language
ISWC'10 Proceedings of the 9th international semantic web conference on The semantic web - Volume Part I
Mathematical and Computer Modelling: An International Journal
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One can partition the class of relational database schemas into tree schemas and cyclic schemas. (These are called acyclic hypergraphs and cyclic hypergraphs elsewhere in the literature.) This partition has interesting implications in query processing, dependency theory, and graph theory.The tree/cyclic partitioning of database schemas originated with a similar partition of equijoin queries. Given an arbitrary equijoin query one can obtain an equivalent query that calculates the natural join of all relations in (an efficiently) derived database; such a query is called a natural join (NJ) query. If the derived database is a tree schema the original query is said to be a tree query, and otherwise a cyclic query.In this paper we analyze query processing consequences of the tree/cyclic partitioning. We are able to argue, qualitatively, that queries which imply a tree schema are easier to process than those implying a cyclic schema. Our results also extend the study of the semijoin operator.