Efficiently updating materialized views
SIGMOD '86 Proceedings of the 1986 ACM SIGMOD international conference on Management of data
SIGMOD '86 Proceedings of the 1986 ACM SIGMOD international conference on Management of data
Combinatorial optimization: algorithms and complexity
Combinatorial optimization: algorithms and complexity
ACM Transactions on Database Systems (TODS)
Query Optimization in Database Systems
ACM Computing Surveys (CSUR)
Graph Algorithms
SIGMOD '83 Proceedings of the 1983 ACM SIGMOD international conference on Management of data
Horizontal data partitioning in database design
SIGMOD '82 Proceedings of the 1982 ACM SIGMOD international conference on Management of data
Common expression analysis in database applications
SIGMOD '82 Proceedings of the 1982 ACM SIGMOD international conference on Management of data
An Extension of Access Paths to Improve Joins and Selections
Proceedings of the Second International Conference on Data Engineering
Updating Derived Relations: Detecting Irrelevant and Autonomously Computable Updates
VLDB '86 Proceedings of the 12th International Conference on Very Large Data Bases
The use of controlled redundancy in self-adaptive databases (temporaries, derived, packrat, r-tree, texture analysis)
Intelligent database caching through the use of page-answers and page-traces
ACM Transactions on Database Systems (TODS)
Query optimization by using derivability in a data warehouse environment
Proceedings of the 3rd ACM international workshop on Data warehousing and OLAP
Enhancing data warehouse performance through query caching
ACM SIGMIS Database
Enhancing data warehouse performance through query caching
ACM SIGMIS Database
Design and Implementation of a Semantic Query Optimizer
IEEE Transactions on Knowledge and Data Engineering
Making the Knowledge Base Systems More Efficient: A Method to Detect Inconsistent Queries
IEEE Transactions on Knowledge and Data Engineering
An Improved Algorithm for Implication Testing Involving Arithmetic Inequalities
IEEE Transactions on Knowledge and Data Engineering
Temporal Query Processing and Optimization in Multiprocessor Database Machines
VLDB '92 Proceedings of the 18th International Conference on Very Large Data Bases
Set-Derivability of Multidimensional Aggregates
DaWaK '99 Proceedings of the First International Conference on Data Warehousing and Knowledge Discovery
WATCHMAN: A Data Warehouse Intelligent Cache Manager
VLDB '96 Proceedings of the 22th International Conference on Very Large Data Bases
A method of aggregate query matching in semantic cache for massive database applications
APPT'05 Proceedings of the 6th international conference on Advanced Parallel Processing Technologies
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Computing queries from derived relations, optimizing queries from a group of queries, and updating materialized views are important database problems and have attracted much attention. One thing common to these problems is their demand to quickly solve the implication problem — given two predicates &sgr;Q and &sgr;&tgr;, can &sgr;Q imply &sgr;&tgr; (&sgr;Q→&sgr;&tgr;)? The implication problem has been solved by converting it into a satisfiability problem. Based on a graph representation, a detailed study of the general implication problem on its own is presented in this paper. We proved that the general implication problem, in which all six comparison operators: =, ≠, , ≤, ≥, as well as conjunctions and disjunctions are allowed, is NP-hard. In the case when “≠” operators are not allowed in &sgr;Q and disjunctions are not allowed in &sgr;&tgr;, a polynomial time algorithm is proposed to solve this restricted implication problem. The influence of the “≠” operator and disjunctions are studied. Our theoretical results show that for some special cases the polynomial complexity algorithm can solve the implication problem which allows the “≠” operator or disjunctions in the predicates. Necessary conditions for detecting when the “≠” operator and disjunctions are allowed are also given. These results are very useful in creating heuristic methods.