Towards an open architecture for LDL
VLDB '89 Proceedings of the 15th international conference on Very large data bases
Managing persistent objects in a multi-level store
SIGMOD '91 Proceedings of the 1991 ACM SIGMOD international conference on Management of data
Predicate migration: optimizing queries with expensive predicates
SIGMOD '93 Proceedings of the 1993 ACM SIGMOD international conference on Management of data
SIGMOD '94 Proceedings of the 1994 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
Optimization techniques for queries with expensive methods
ACM Transactions on Database Systems (TODS)
Statistical estimators for relational algebra expressions
Proceedings of the seventh ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Optimization of queries with user-defined predicates
ACM Transactions on Database Systems (TODS)
Access path selection in a relational database management system
SIGMOD '79 Proceedings of the 1979 ACM SIGMOD international conference on Management of data
A Polynomial Time Algorithm for Optimizing Join Queries
Proceedings of the Ninth International Conference on Data Engineering
Optimization of Nonrecursive Queries
VLDB '86 Proceedings of the 12th International Conference on Very Large Data Bases
Sampling-Based Estimation of the Number of Distinct Values of an Attribute
VLDB '95 Proceedings of the 21th International Conference on Very Large Data Bases
Optimization of Queries Including ADT Functions
Proceedings of the Second International Symposium on Database Systems for Advanced Applications
Optimization of multi-version expensive predicates
Proceedings of the 2007 ACM SIGMOD international conference on Management of data
UMQL: A Unified Multimedia Query Language
SITIS '07 Proceedings of the 2007 Third International IEEE Conference on Signal-Image Technologies and Internet-Based System
GMQL: A graphical multimedia query language
Knowledge-Based Systems
Large-scale similarity-based join processing in multimedia databases
MMM'12 Proceedings of the 18th international conference on Advances in Multimedia Modeling
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Based on the assumption that selections are zero-expense operations, "selection pushdown" rules, which apply selections in random order before as many joins as possible in order to reduce subsequent join costs, have been widely applied in traditional query optimization methods. However, in multimedia information systems, selections generally contain expensive multimedia operations, making "pushdown" rules no longer able to produce optimal query execution plan. Therefore, we in this paper develop a theory for optimizing queries with expensive multimedia operations, which can establish the optimal placement of each multimedia operation in a query plan by the comprehensive consideration of selectivity and unit execution cost of each operation. Then we present an algorithm for the theory and implement it in a prototype system. Experimental results show that, compared with traditional optimization algorithms, our algorithm not only has the modest time complexity that is polynomial in the number of multimedia operations in a query plan, but also can reduce the execution cost of a query plan by orders of magnitude.