The EXODUS optimizer generator
SIGMOD '87 Proceedings of the 1987 ACM SIGMOD international conference on Management of data
A rule-based view of query optimization
SIGMOD '87 Proceedings of the 1987 ACM SIGMOD international conference on Management of data
Grammar-like functional rules for representing query optimization alternatives
SIGMOD '88 Proceedings of the 1988 ACM SIGMOD international conference on Management of data
Towards an efficient evaluation of general queries: quantifier and disjunction processing revisited
SIGMOD '89 Proceedings of the 1989 ACM SIGMOD international conference on Management of data
Extensible query processing in starburst
SIGMOD '89 Proceedings of the 1989 ACM SIGMOD international conference on Management of data
Queries and query processing in object-oriented database systems
ACM Transactions on Information Systems (TOIS)
The C++ programming language (2nd ed.)
The C++ programming language (2nd ed.)
Rule-based optimization and query processing in an extensible geometric database system
ACM Transactions on Database Systems (TODS)
A general framework for the optimization of object-oriented queries
SIGMOD '92 Proceedings of the 1992 ACM SIGMOD international conference on Management of data
Query evaluation techniques for large databases
ACM Computing Surveys (CSUR)
Predicate migration: optimizing queries with expensive predicates
SIGMOD '93 Proceedings of the 1993 ACM SIGMOD international conference on Management of data
Experiences building the open OODB query optimizer
SIGMOD '93 Proceedings of the 1993 ACM SIGMOD international conference on Management of data
Optimizing disjunctive queries with expensive predicates
SIGMOD '94 Proceedings of the 1994 ACM SIGMOD international conference on Management of data
Query execution techniques for caching expensive methods
SIGMOD '96 Proceedings of the 1996 ACM SIGMOD international conference on Management of data
The object database standard: ODMG 2.0
The object database standard: ODMG 2.0
Query processing in a system for distributed databases (SDD-1)
ACM Transactions on Database Systems (TODS)
Query optimization in star computer networks
ACM Transactions on Database Systems (TODS)
Query Optimization in Database Systems
ACM Computing Surveys (CSUR)
An optimal evaluation of Boolean expressions in an online query system
Communications of the ACM
Query Processing for Advanced Database Systems
Query Processing for Advanced Database Systems
Access path selection in a relational database management system
SIGMOD '79 Proceedings of the 1979 ACM SIGMOD international conference on Management of data
Advanced Query Processing in Object Bases Using Access Support Relations
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
Query Optimization by Predicate Move-Around
VLDB '94 Proceedings of the 20th International Conference on Very Large Data Bases
Bypassing Joins in Disjunctive Queries
VLDB '95 Proceedings of the 21th International Conference on Very Large Data Bases
Optimization of Queries with User-defined Predicates
VLDB '96 Proceedings of the 22th International Conference on Very Large Data Bases
Control of an Extensible Query Optimizer: A Planning-Based Approach
VLDB '93 Proceedings of the 19th International Conference on Very Large Data Bases
The Volcano Optimizer Generator: Extensibility and Efficient Search
Proceedings of the Ninth International Conference on Data Engineering
The VLDB Journal — The International Journal on Very Large Data Bases
On the Optimal Ordering of Maps and Selections under Factorization
ICDE '05 Proceedings of the 21st International Conference on Data Engineering
Foundations and Trends in Databases
Expert Systems with Applications: An International Journal
Topological feature vectors for exploring topological relationships
International Journal of Geographical Information Science
Kappa-join: efficient execution of existential quantification in XML query languages
XSym'06 Proceedings of the 4th international conference on Database and XML Technologies
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It is striking that the optimization of disjunctive queries驴i.e., those which contain at least one or-connective in the query predicate驴has been vastly neglected in the literature, as well as in commercial systems. In this paper, we propose a novel technique, called bypass processing, for evaluating such disjunctive queries. The bypass processing technique is based on new selection and join operators that produce two output streams: the true-stream with tuples satisfying the selection (join) predicate and the false-stream with tuples not satisfying the corresponding predicate. Splitting the tuple streams in this way enables us to 驴bypass驴 costly predicates whenever the 驴fate驴 of the corresponding tuple (stream) can be determined without evaluating this predicate. In the paper, we show how to systematically generate bypass evaluation plans utilizing a bottom-up building block approach. We show that our evaluation technique allows to incorporate the standard SQL semantics of null values. For this, we devise two different approaches: One is based on explicitly incorporating three-valued logic into the evaluation plans; the other one relies on two-valued logic by 驴moving驴 all negations to atomic conditions of the selection predicate. We describe how to extend an iterator-based query engine to support bypass evaluation with little extra overhead. This query engine was used to quantitatively evaluate the bypass evaluation plans against the traditional evaluation techniques utilizing a CNF- or DNF-based query predicate.