Distributed databases principles and systems
Distributed databases principles and systems
View indexing in relational databases
ACM Transactions on Database Systems (TODS)
Joined normal form: a storage encoding for relational databasess
ACM Transactions on Database Systems (TODS)
System R: relational approach to database management
ACM Transactions on Database Systems (TODS)
The design and implementation of INGRES
ACM Transactions on Database Systems (TODS)
Equivalences Among Relational Expressions with the Union and Difference Operators
Journal of the ACM (JACM)
Common expression analysis in database applications
SIGMOD '82 Proceedings of the 1982 ACM SIGMOD international conference on Management of data
Theory of Relational Databases
Theory of Relational Databases
Rewriting Unions of General Conjunctive Queries Using Views
EDBT '02 Proceedings of the 8th International Conference on Extending Database Technology: Advances in Database Technology
Form-Based Proxy Caching for Database-Backed Web Sites
Proceedings of the 27th International Conference on Very Large Data Bases
Scalable and Dynamic Grouping of Continual Queries
ADVIS '02 Proceedings of the Second International Conference on Advances in Information Systems
Multiplex: A Formal Model for Multidatabases and Its Implementation
NGIT '99 Proceedings of the 4th International Workshop on Next Generation Information Technologies and Systems
Modelling and Optimisation Issues for Multidimensional Databases
CAiSE '00 Proceedings of the 12th International Conference on Advanced Information Systems Engineering
Answering Multidimensional Queries on Cubes Using Other Cubes
SSDBM '00 Proceedings of the 12th International Conference on Scientific and Statistical Database Management
Load distribution of analytical query workloads for database cluster architectures
EDBT '08 Proceedings of the 11th international conference on Extending database technology: Advances in database technology
Form-based proxy caching for database-backed web sites: keywords and functions
The VLDB Journal — The International Journal on Very Large Data Bases
Supporting views in data stream management systems
ACM Transactions on Database Systems (TODS)
Query Optimization through Cached Queries for Object-Oriented Query Language SBQL
SOFSEM '10 Proceedings of the 36th Conference on Current Trends in Theory and Practice of Computer Science
Caching and Materialization for Web Databases
Foundations and Trends in Databases
Describing and deriving certain answers over partial databases
Journal of Intelligent Information Systems
Power efficiency through tuple ranking in wireless sensor network monitoring
Distributed and Parallel Databases
Optimizing query shortcuts in RDF databases
ESWC'11 Proceedings of the 8th extended semantic web conference on The semanic web: research and applications - Volume Part II
CASCON '12 Proceedings of the 2012 Conference of the Center for Advanced Studies on Collaborative Research
Easy freshness with Pequod cache joins
NSDI'14 Proceedings of the 11th USENIX Conference on Networked Systems Design and Implementation
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Assume that a set of derived relations are available in stored form. Given a query (or subquery), can it be computed from the derived rela- tions and, if so, how? Variants of this problem arise in several areas of query processing. Relation fragments stored at a site in a distributed database system, data- base snapshots, and intermediate results obtained dur- ing the processing of a query are all examples of stored, derived relations. In this paper we give neces- sary and sufficient conditions for when a query is com- putable from a single derived relation. It is assumed that both the query and the derived relation are defined by PSJ-expressions, that is, relational algebra expressions involving only projections, selections, and joins, in any combination. The solution is constructive: not only does it tell whether the query is computable or not, but it also shows how to compute it.