On Relational Support for XML Publishing: Beyond Sorting and Tagging
- Surajit Chaudhuri ,
- Raghav Kaushik ,
- Jeffrey F. Naughton
SIGMOD |
Published by Association for Computing Machinery, Inc.
In this paper, we study whether the need for e cient XML
publishing brings any new requirements for relational query
engines, or if sorting query results in the relational engine
and tagging them in middleware is su cient. We observe
that the mismatch between the XML data model and the
relational model requires relational engines to be enhanced
for e ciency. Speci cally, they need to support relation-
valued variables. We discuss how such support can be pro-
vided through the addition of an operator, GApply, with
minimal extensions to existing relational engines. We dis-
cuss how the operator may be exposed in SQL syntax and
provide a comprehensive study of optimization rules that
govern this operator. We report the results of a prelimi-
nary performance evaluation showing the speedup obtained
through our approach and the e ectiveness of our optimiza-
tion rules.
Copyright © 2003 by the Association for Computing Machinery, Inc. Permission to make digital or hard copies of part or all of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than ACM must be honored. Abstracting with credit is permitted. To copy otherwise, to republish, to post on servers, or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from Publications Dept, ACM Inc., fax +1 (212) 869-0481, or permissions@acm.org. The definitive version of this paper can be found at ACM's Digital Library --http://www.acm.org/dl/.