The XCDE search engine
- XCDE library developed at the
Department of Computer Science, University of Pisa (prof. Paolo Ferragina).
- Best suited for collections of a limited number of large size documents
- Query language
oriented
mainly to the processing and management of textual data
- Query syntax:
- similar to SQL: SELECT-FROM-RETURN
- SELECT clause specified by means of an XML piece of well-formed text
- implements most of the IR
functionalities detailed in the W3C Working Draft of XQuery
and XPath Full-Text Requirements, as
well as other powerful string-based queries
(regular expressions and error matches).
- output of the query (the snippet) can be formatted within
the RETURN clause which, again, includes an XML piece of
well-formed text.
- A special attribute named xml_var (pivot) is added to elements within the SELECT
clause in order to identify some "interesting points" in each
document subtree that matches the query.
Pivots are used
in the RETURN clause to indicate the way in which these points in
the matching subtree must be visualized.
