Query processing in a system for distributed databases (SDD-1)
ACM Transactions on Database Systems (TODS)
Introduction to a system for distributed databases (SDD-1)
ACM Transactions on Database Systems (TODS)
Using Semi-Joins to Solve Relational Queries
Journal of the ACM (JACM)
The Design and Analysis of Computer Algorithms
The Design and Analysis of Computer Algorithms
Assumptions in relational database theory
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
ACM Computing Surveys (CSUR)
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
Load balancing in a locally distributed DB system
SIGMOD '86 Proceedings of the 1986 ACM SIGMOD international conference on Management of data
PODS '89 Proceedings of the eighth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Solving queries by tree projections
ACM Transactions on Database Systems (TODS)
Adaptive Algorithms for Join Processing in Distributed Database Systems
Distributed and Parallel Databases
Using join operations as reducers in distributed query processing
DPDS '90 Proceedings of the second international symposium on Databases in parallel and distributed systems
Query Optimization in Database Systems
ACM Computing Surveys (CSUR)
Query processing utilizing dependencies and horizontal decomposition
SIGMOD '83 Proceedings of the 1983 ACM SIGMOD international conference on Management of data
A Graph Theoretical Approach to Determine a Join Reducer Sequence in Distributed Query Processing
IEEE Transactions on Knowledge and Data Engineering
On the Complexity of Distributed Query Optimization
IEEE Transactions on Knowledge and Data Engineering
Interleaving a Join Sequence with Semijoins in Distributed Query Processing
IEEE Transactions on Parallel and Distributed Systems
Evaluating Recursive Queries in Distributed Databases
IEEE Transactions on Knowledge and Data Engineering
Combining Joint and Semi-Join Operations for Distributed Query Processing
IEEE Transactions on Knowledge and Data Engineering
Processing Inequality Queries Based on Generalized Semi-Joins
VLDB '84 Proceedings of the 10th International Conference on Very Large Data Bases
Posse: A Framework for Optimizing Incremental View Maintenance at Data Warehouse
DaWaK '99 Proceedings of the First International Conference on Data Warehousing and Knowledge Discovery
AFIPS '84 Proceedings of the July 9-12, 1984, national computer conference and exposition
A database machine based on the data distribution approach
AFIPS '84 Proceedings of the July 9-12, 1984, national computer conference and exposition
The VLDB Journal — The International Journal on Very Large Data Bases
Multiple sensitive association protection in the outsourced database
DASFAA'10 Proceedings of the 15th international conference on Database Systems for Advanced Applications - Volume Part II
Generating query plans for distributed query processing using genetic algorithm
ICICA'11 Proceedings of the Second international conference on Information Computing and Applications
Allocating relations in a distributed database system
Mathematical and Computer Modelling: An International Journal
Mathematical and Computer Modelling: An International Journal
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In distributed database systems, the cost to process a query is mainly determined by the amount of communication. Semi-join is a very useful tool to reduce the cost of joins in such systems. There are, however, queries called cyclic ones which cannot be processed by semi-joins only. In this paper the concept of generalized semi-joins is introduced to solve such a problem. To handle an arbitrary cyclic query, first a spanning tree is selected in the corresponding query graph and then generalized semi-joins are applied in the order determined by the tree. Processing of cyclic queries, however, requires more communication cost than processing of tree queries, since in the former case we need to transmit attribute values which are not required in the latter case. A procedure to reduce the communication cost of such additional data is developed, which will make the generalized semi-join based procedures practical.