Distributed databases principles and systems
Distributed databases principles and systems
On the optimal nesting order for computing N-relational joins
ACM Transactions on Database Systems (TODS)
Query Processing in a Fragmented Relational Distributed System: Mermaid
IEEE Transactions on Software Engineering - Annals of discrete mathematics, 24
Depth-first iterative-deepening: an optimal admissible tree search
Artificial Intelligence
Query optimization by simulated annealing
SIGMOD '87 Proceedings of the 1987 ACM SIGMOD international conference on Management of data
Algorithms for clustering data
Algorithms for clustering data
Optimization of large join queries
SIGMOD '88 Proceedings of the 1988 ACM SIGMOD international conference on Management of data
Simulated annealing and Boltzmann machines: a stochastic approach to combinatorial optimization and neural computing
Dynamic query evaluation plans
SIGMOD '89 Proceedings of the 1989 ACM SIGMOD international conference on Management of data
Optimization of large join queries: combining heuristics and combinatorial techniques
SIGMOD '89 Proceedings of the 1989 ACM SIGMOD international conference on Management of data
Optimizing SQL queries for parallel execution
ACM SIGMOD Record
Randomized algorithms for optimizing large join queries
SIGMOD '90 Proceedings of the 1990 ACM SIGMOD international conference on Management of data
Critical issues in multidatabase systems
Information Sciences: an International Journal - Special issue on information sciences—past, present, and future
SIGMOD '91 Proceedings of the 1991 ACM SIGMOD international conference on Management of data
Parallel database systems: the future of database processing or a passing fad?
ACM SIGMOD Record - Directions for future database research & development
Query optimization for parallel execution
SIGMOD '92 Proceedings of the 1992 ACM SIGMOD international conference on Management of data
On global multidatabase query optimization
ACM SIGMOD Record
Query evaluation techniques for large databases
ACM Computing Surveys (CSUR)
Query optimization and processing in federated database systems
CIKM '93 Proceedings of the second international conference on Information and knowledge management
Reducing multidatabase query response time by tree balancing
SIGMOD '95 Proceedings of the 1995 ACM SIGMOD international conference on Management of data
Simulated annealing and combinatorial optimization
DAC '86 Proceedings of the 23rd ACM/IEEE Design Automation Conference
An effective algorithm for parallelizing sort merge joins in the presence of data skew
DPDS '90 Proceedings of the second international symposium on Databases in parallel and distributed systems
Optimizing multi-join queries in parallel relational databases
PDIS '93 Proceedings of the second international conference on Parallel and distributed information systems
Genetic Algorithms in Search, Optimization and Machine Learning
Genetic Algorithms in Search, Optimization and Machine Learning
Mermaid - Experiences with Network Operation
Proceedings of the Second International Conference on Data Engineering
R* Optimizer Validation and Performance Evaluation for Distributed Queries
VLDB '86 Proceedings of the 12th International Conference on Very Large Data Bases
Optimization of Nonrecursive Queries
VLDB '86 Proceedings of the 12th International Conference on Very Large Data Bases
A Formal Model of Trade-off between Optimization and Execution Costs in Semantic Query Optimization
VLDB '88 Proceedings of the 14th International Conference on Very Large Data Bases
Optimization of Multi-Way Join Queries for Parallel Execution
VLDB '91 Proceedings of the 17th International Conference on Very Large Data Bases
Extending the Search Strategy in a Query Optimizer
VLDB '91 Proceedings of the 17th International Conference on Very Large Data Bases
Query Optimization in a Heterogeneous DBMS
VLDB '92 Proceedings of the 18th International Conference on Very Large Data Bases
Distributed Query Processing Strategies in Mermaid, A Frontend to Data Management Systems
Proceedings of the First International Conference on Data Engineering
The Volcano Optimizer Generator: Extensibility and Efficient Search
Proceedings of the Ninth International Conference on Data Engineering
Overview of multidatabase transaction management
Overview of multidatabase transaction management
Distributed and Parallel Databases
UBIQUEST, for rapid prototyping of networking applications
Proceedings of the 16th International Database Engineering & Applications Sysmposium
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Global query execution in a multidatabase system can be doneparallelly, as all the local databases are independent. In this paper, acost model that considers parallel execution of subqueries for a globalquery is developed. In order to obtain maximum parallelism in queryexecution, it is required to find a query execution plan that isrepresented in the form of a bushy tree and this query tree should bebalanced to the maximal possible extent with respect to execution time. A new bottom up approach called Agglomerative Approach (AA) is proposed toconstruct balanced bushy trees with respect to execution time. By thedeterministic nature of this approach, it generates local optimal solutions. This local minima problem will be severe in the case of graph queries, i.e., queries that are represented with a graph structure. ASimulated annealing Approach (SA) is employed to obtain a (near) optimalsolution. These approaches (AA and SA) are suitable for handling on-lineand off-line queries respectively. A Hybrid Approach (HA), that is anintegration of AA and SA, is proposed to optimize queries for which theestimated time to be spent on optimization is known a priori. Resultsobtained with AA and SA on both tree and graph structured queries arepresented.