Optimization of query evaluation algorithms
ACM Transactions on Database Systems (TODS)
Decomposition—a strategy for query processing
ACM Transactions on Database Systems (TODS)
Approximating block accesses in database organizations
Communications of the ACM
Access path selection in a relational database management system
SIGMOD '79 Proceedings of the 1979 ACM SIGMOD international conference on Management of data
A new way to compute the product and join of relations
SIGMOD '80 Proceedings of the 1980 ACM SIGMOD international conference on Management of data
Using the Entity-Relationship Model for Implementing Multi-Model Database Systems
ER '81 Proceedings of the Second International Conference on the Entity-Relationship Approach to Information Modeling and Analysis
Analysis of indexed sequential and direct access file organizations
SIGFIDET '74 Proceedings of the 1974 ACM SIGFIDET (now SIGMOD) workshop on Data description, access and control
GENESIS: An Extensible Database Management System
IEEE Transactions on Software Engineering
On the translation of relational queries into iterative programs
ACM Transactions on Database Systems (TODS)
Formal semantics of SQL queries
ACM Transactions on Database Systems (TODS)
Optimizing queries over multimedia repositories
SIGMOD '96 Proceedings of the 1996 ACM SIGMOD international conference on Management of data
Query Optimization in Database Systems
ACM Computing Surveys (CSUR)
Query Optimization and Execution Plan Generation in Object-Oriented Data Management Systems
IEEE Transactions on Knowledge and Data Engineering
Efficient Queries over Web Views
IEEE Transactions on Knowledge and Data Engineering
Extending the Algebraic Framework of Query Processing to Handle Outerjoins
VLDB '84 Proceedings of the 10th International Conference on Very Large Data Bases
Anatomy of a Mudular Multiple Query Optimizer
VLDB '88 Proceedings of the 14th International Conference on Very Large Data Bases
Measuring the Complexity of Join Enumeration in Query Optimization
VLDB '90 Proceedings of the 16th International Conference on Very Large Data Bases
A Blackboard Architecture for Query Optimization in Object Bases
VLDB '93 Proceedings of the 19th International Conference on Very Large Data Bases
The Fittest Survives: An Adaptive Approach to Query Optimization
VLDB '95 Proceedings of the 21th International Conference on Very Large Data Bases
Optimizing Top-k Selection Queries over Multimedia Repositories
IEEE Transactions on Knowledge and Data Engineering
Local and global query optimization mechanisms for relational databases
VLDB '85 Proceedings of the 11th international conference on Very Large Data Bases - Volume 11
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We describe an optimizer for relational queries to databases stored as flat files and Codasyl networks. We include sophisticated manipulations on a broad range of direct access structures (DAS's). To achieve this with minimum additional code, we allow operations like sort, scan, and join to apply to DAS's, and categorize indexes and other DAS's in terms of the operations which can be performed on them. Our storage model, based on indivisible units of access and a small set of associated physical operators, provides a uniform interface to both relational and Codasyl storage mechanisms. The optimizer derives a sequence of internal data structures at successively more detailed levels. For a given query, a graph representing an overview of alternative joins is constructed, and then used to derive a physical graph which considers the physical attributes (location and sort order) of the data objects involved. Using cost predictions and other heuristics, the optimizer prunes the physical graph to produce a final access strategy tree. This layered approach and reliance on primitive operators make explicit (and permit changes to) the universe of possible strategies for the query at hand, and ease extension of the optimizer to new storage structures.