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BNCOD
2006
55views Database» more  BNCOD 2006»
14 years 9 days ago
On the Optimal Ordering of Maps, Selections, and Joins Under Factorization
We examine the problem of producing the optimal evaluation order for queries containing joins, selections, and maps. Specifically, we look at the case where common subexpressions i...
Thomas Neumann, Sven Helmer, Guido Moerkotte
ICDE
2005
IEEE
113views Database» more  ICDE 2005»
15 years 7 days ago
On the Optimal Ordering of Maps and Selections under Factorization
The query optimizer of a database system is confronted with two aspects when handling user-defined functions (UDFs) in query predicates: the vast differences in evaluation costs b...
Thomas Neumann, Sven Helmer, Guido Moerkotte
CIKM
2005
Springer
14 years 4 months ago
Selectivity-based partitioning: a divide-and-union paradigm for effective query optimization
Modern query optimizers select an efficient join ordering for a physical execution plan based essentially on the average join selectivity factors among the referenced tables. In ...
Neoklis Polyzotis
GVD
2003
151views Database» more  GVD 2003»
14 years 8 days ago
Bridging the GAP Between Relational and Native XML Storage with Staircase Join
Several mapping schemes have recently been proposed to store XML data in relational tables. Relational database systems are readily available and can handle vast amounts of data v...
Jens Teubner, Torsten Grust, Maurice van Keulen
SIGMOD
2004
ACM
157views Database» more  SIGMOD 2004»
14 years 11 months ago
Adaptive Ordering of Pipelined Stream Filters
We consider the problem of pipelined filters, where a continuous stream of tuples is processed by a set of commutative filters. Pipelined filters are common in stream applications...
Shivnath Babu, Rajeev Motwani, Kamesh Munagala, It...