Statistical profile estimation in database systems
ACM Computing Surveys (CSUR)
Logic-based approach to semantic query optimization
ACM Transactions on Database Systems (TODS)
Deriving production rules for constraint maintenance
Proceedings of the sixteenth international conference on Very large databases
Automatic generation of production rules for integrity maintenance
ACM Transactions on Database Systems (TODS)
Answering queries using views (extended abstract)
PODS '95 Proceedings of the fourteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Balancing histogram optimality and practicality for query result size estimation
SIGMOD '95 Proceedings of the 1995 ACM SIGMOD international conference on Management of data
Fundamental techniques for order optimization
SIGMOD '96 Proceedings of the 1996 ACM SIGMOD international conference on Management of data
Improved histograms for selectivity estimation of range predicates
SIGMOD '96 Proceedings of the 1996 ACM SIGMOD international conference on Management of data
Using inductive learning to generate rules for semantic query optimization
Advances in knowledge discovery and data mining
Wavelet-based histograms for selectivity estimation
SIGMOD '98 Proceedings of the 1998 ACM SIGMOD international conference on Management of data
Multi-dimensional selectivity estimation using compressed histogram information
SIGMOD '99 Proceedings of the 1999 ACM SIGMOD international conference on Management of data
Join synopses for approximate query answering
SIGMOD '99 Proceedings of the 1999 ACM SIGMOD international conference on Management of data
Exploiting constraint-like data characterizations in query optimization
SIGMOD '01 Proceedings of the 2001 ACM SIGMOD international conference on Management of data
Dynamic multidimensional histograms
Proceedings of the 2002 ACM SIGMOD international conference on Management of data
Computers and Intractability: A Guide to the Theory of NP-Completeness
Computers and Intractability: A Guide to the Theory of NP-Completeness
Access path selection in a relational database management system
SIGMOD '79 Proceedings of the 1979 ACM SIGMOD international conference on Management of data
An optimizing prolog front-end to a relational query system
SIGMOD '84 Proceedings of the 1984 ACM SIGMOD international conference on Management of data
Design and Implementation of a Semantic Query Optimizer
IEEE Transactions on Knowledge and Data Engineering
Automatic Knowledge Acquisition and Maintenance for Semantic Query Optimization
IEEE Transactions on Knowledge and Data Engineering
Learning Transformation Rules for Semantic Query Optimization: A Data-Driven Approach
IEEE Transactions on Knowledge and Data Engineering
Using Type Inference and Induced Rules to Provide Intensional Answers
Proceedings of the Seventh International Conference on Data Engineering
Optimizing Queries with Materialized Views
ICDE '95 Proceedings of the Eleventh International Conference on Data Engineering
Discovery and Application of Check Constraints in DB2
Proceedings of the 17th International Conference on Data Engineering
VLDB '98 Proceedings of the 24rd International Conference on Very Large Data Bases
Implementation of Two Semantic Query Optimization Techniques in DB2 Universal Database
VLDB '99 Proceedings of the 25th International Conference on Very Large Data Bases
Automated Selection of Materialized Views and Indexes in SQL Databases
VLDB '00 Proceedings of the 26th International Conference on Very Large Data Bases
Knowledge Discovery in Databases: An Attribute-Oriented Approach
VLDB '92 Proceedings of the 18th International Conference on Very Large Data Bases
Semantic Data Caching and Replacement
VLDB '96 Proceedings of the 22th International Conference on Very Large Data Bases
Answering Queries with Aggregation Using Views
VLDB '96 Proceedings of the 22th International Conference on Very Large Data Bases
Selectivity Estimation Without the Attribute Value Independence Assumption
VLDB '97 Proceedings of the 23rd International Conference on Very Large Data Bases
An Approach to Deriving Object Hierarchies from Database Schema and Contents
ISMIS '91 Proceedings of the 6th International Symposium on Methodologies for Intelligent Systems
Recommending Materialized Views and Indexes with IBM DB2 Design Advisor
ICAC '04 Proceedings of the First International Conference on Autonomic Computing
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A join of two relations in real databases is usually much smaller than their Cartesian product. This means that most of the combinations of tuples in the crossproduct of the respective relations do not appear together in the join result. We characterize these combinations as ranges of attributes that do not appear together. We sketch an algorithm for finding such combinations and present experimental results from real data sets. We then explore two potential applications of this knowledge in query processing. In the first application, we model empty joins as materialized views, we show how they can be used for query optimization. In the second application, we propose a strategy that uses information about empty joins for an improved join selectivity estimation.