Presentation by: Fatih Çakmak Mustafa Bilge. Introduction. XML Message Brokers: Central exchange point for messages Filtering: matches messages to a large set of queries that represent the data interests. Transformation: restructures matched messages.
Tens of thousands simultaneous queries.
Individual processing of queries is not adequate.
Shared processing of path expressions.
In the paper, alternatives for building customization functionality on shared path filtering systems.
Can we benefit from shared paths during transformations?Introduction
YFilter guarantees that path-tuples in each stream are produced such that the node ids in the last field of the path-tuples appear in monotonically increasing order.
$s/title => //section/title
$s/figure/title => //section/figure/title
$s//section//title => //section//section/title
$s/figure => //section/figure
Path-tuples From Matching
Requires examining the queries.
Checked by examining a DTD
2.1 Shared GroupBy for OuterJoinSelect
2.2 Selection-DupElim pull up
2.3 Shared selection
So must be “figure/image”
Only Path Sharing
With Plan Sharing