On conjunctive queries containing inequalities
Journal of the ACM (JACM)
The complexity of querying indefinite data about linearly ordered domains
PODS '92 Proceedings of the eleventh ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Constraint checking with partial information
PODS '94 Proceedings of the thirteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Answering queries using views (extended abstract)
PODS '95 Proceedings of the fourteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Answering queries using limited external query processors (extended abstract)
PODS '96 Proceedings of the fifteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Answering recursive queries using views
PODS '97 Proceedings of the sixteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
On the complexity of the containment problem for conjunctive queries with built-in predicates
PODS '98 Proceedings of the seventeenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Equivalences Among Relational Expressions with the Union and Difference Operators
Journal of the ACM (JACM)
Generating efficient plans for queries using views
SIGMOD '01 Proceedings of the 2001 ACM SIGMOD international conference on Management of data
Answering queries using views with arithmetic comparisons
Proceedings of the twenty-first ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
An algorithm for answering queries efficiently using views
ADC '01 Proceedings of the 12th Australasian database conference
ICDE '96 Proceedings of the Twelfth International Conference on Data Engineering
Tableau Techniques for Querying Information Sources through Global Schemas
ICDT '99 Proceedings of the 7th International Conference on Database Theory
Answering Queries Using Materialized Views with Disjunctions
ICDT '99 Proceedings of the 7th International Conference on Database Theory
Queries Independent of Updates
VLDB '93 Proceedings of the 19th International Conference on Very Large Data Bases
Querying Heterogeneous Information Sources Using Source Descriptions
VLDB '96 Proceedings of the 22th International Conference on Very Large Data Bases
MiniCon: A scalable algorithm for answering queries using views
The VLDB Journal — The International Journal on Very Large Data Bases
Answering queries using views: A survey
The VLDB Journal — The International Journal on Very Large Data Bases
Optimal implementation of conjunctive queries in relational data bases
STOC '77 Proceedings of the ninth annual ACM symposium on Theory of computing
Object/relational query optimization with chase and backchase
Object/relational query optimization with chase and backchase
Xml query reformulation over mixed and redundant storage
Xml query reformulation over mixed and redundant storage
Rewriting queries using views in the presence of arithmetic comparisons
Theoretical Computer Science
Querying data sources that export infinite sets of views
Proceedings of the 12th International Conference on Database Theory
Approximate Rewriting of Queries Using Views
ADBIS '09 Proceedings of the 13th East European Conference on Advances in Databases and Information Systems
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The problem of rewriting queries using views has received significant attention because of its applications in a wide variety of data-management problems. For select-project-join SQL (a.k.a. conjunctive) queries and views, there are efficient algorithms in the literature, which find equivalent and maximally contained rewritings. In the presence of arithmetic comparisons (ACs) the problem becomes more complex. We do not know how to find maximally contained rewritings in the general case. There are algorithms which find maximally contained rewritings only for special cases such as when ACs are restricted to be semi-interval. However, we know that the problem of finding an equivalent rewriting (if there exists one) in the presence of ACs is decidable, yet still doubly exponential. This complexity calls for an efficient algorithm which will perform better on average than the complete enumeration algorithm. In this work we present such an algorithm which is sound and complete. Its efficiency lies in that it considers fewer candidate rewritings because it includes a preliminary test to decide for each view whether it is potentially useful in some rewriting.