TY - GEN
T1 - Navigation-driven evaluation of virtual mediated views
AU - Ludäscher, Bertram
AU - Papakonstantinou, Yannis
AU - Velikhov, Pavel
N1 - Publisher Copyright:
© Springer-Verlag Berlin Heidelberg 2000.
PY - 2000
Y1 - 2000
N2 - The MIX mediator systems incorporates a novel framework for navigation-driven evaluation of virtual mediated views. Its architecture allows the on-demand computation of views and query results as the user navigates them. The evaluation scheme minimizes superfluous source access through the use of lazy mediators that translate incoming client navigations on virtual XML views into navigations on lower level mediators or wrapped sources. The proposed demand-driven approach is inevitable for handling up-to-date mediated views of large Web sources or query results. The non-materialization of the query answer is transparent to the client application since clients can navigate the query answer using a subset of the standard DOM API for XML documents. We elaborate on query evaluation in such a framework and show how algebraic plans can be implemented as trees of lazy mediators. Finally, we present a new buffering technique that can mediate between the ne granularity of DOM navigations and the coarse granularity of real world sources. This drastically reduces communication overhead and also simplifies wrapper development. An implementation of the system is available on the Web.
AB - The MIX mediator systems incorporates a novel framework for navigation-driven evaluation of virtual mediated views. Its architecture allows the on-demand computation of views and query results as the user navigates them. The evaluation scheme minimizes superfluous source access through the use of lazy mediators that translate incoming client navigations on virtual XML views into navigations on lower level mediators or wrapped sources. The proposed demand-driven approach is inevitable for handling up-to-date mediated views of large Web sources or query results. The non-materialization of the query answer is transparent to the client application since clients can navigate the query answer using a subset of the standard DOM API for XML documents. We elaborate on query evaluation in such a framework and show how algebraic plans can be implemented as trees of lazy mediators. Finally, we present a new buffering technique that can mediate between the ne granularity of DOM navigations and the coarse granularity of real world sources. This drastically reduces communication overhead and also simplifies wrapper development. An implementation of the system is available on the Web.
UR - http://www.scopus.com/inward/record.url?scp=84937431466&partnerID=8YFLogxK
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U2 - 10.1007/3-540-46439-5_10
DO - 10.1007/3-540-46439-5_10
M3 - Conference contribution
AN - SCOPUS:84937431466
T3 - Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
SP - 150
EP - 165
BT - Advances in Database Technology - EDBT 2000 - 7th International Conference on Extending Database Technology, Proceedings
A2 - Zaniolo, Carlo
A2 - Lockemann, Peter C.
A2 - Scholl, Marc H.
A2 - Grust, Torsten
PB - Springer
T2 - 7th International Conference on Extending Database Technology, EDBT 2000
Y2 - 27 March 2000 through 31 March 2000
ER -