+
+ <table id="table-features-overview" frame="top">
+ <title>&zebra; Features Overview</title>
+ <tgroup cols="4">
+ <thead>
+ <row>
+ <entry>Feature</entry>
+ <entry>Availability</entry>
+ <entry>Notes</entry>
+ <entry>Reference</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry>Boolean query language</entry>
+ <entry>&cql; and &rpn;/&pqf;</entry>
+ <entry>The type-1 Reverse Polish Notation (&rpn;)
+ and it's textual representation Prefix Query Format (&pqf;) are
+ supported. The Common Query Language (&cql;) can be configured as
+ a mapping from &cql; to &rpn;/&pqf;</entry>
+ <entry><xref linkend="querymodel-query-languages-pqf"/>
+ <xref linkend="querymodel-cql-to-pqf"/></entry>
+ </row>
+ <row>
+ <entry>Operation types</entry>
+ <entry> &z3950;/&sru; explain, search, and scan</entry>
+ <entry></entry>
+ <entry><xref linkend="querymodel-operation-types"/></entry>
+ </row>
+ <row>
+ <entry>Recursive boolean query tree</entry>
+ <entry>&cql; and &rpn;/&pqf;</entry>
+ <entry>Both &cql; and &rpn;/&pqf; allow atomic query parts (&apt;) to
+ be combined into complex boolean query trees</entry>
+ <entry><xref linkend="querymodel-rpn-tree"/></entry>
+ </row>
+ <row>
+ <entry>Large databases</entry>
+ <entry>64 file pointers assure that register files can extend
+ the 2 GB limit. Logical files can be
+ automatically partitioned over multiple disks, thus allowing for
+ large databases.</entry>
+ <entry></entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry>Complex semi-structured Documents</entry>
+ <entry>&xml; and &grs1; Documents</entry>
+ <entry>Both &xml; and &grs1; documents exhibit a &dom; like internal
+ representation allowing for complex indexing and display rules</entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry>Database updates</entry>
+ <entry>live, incremental updates</entry>
+ <entry>Robust updating - records can be added and deleted ``on the fly''
+ without rebuilding the index from scratch.
+ Records can be safely updated even while users are accessing
+ the server.
+ The update procedure is tolerant to crashes or hard interrupts
+ during database updating - data can be reconstructed following
+ a crash.</entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry>Input document formats</entry>
+ <entry>&xml;, &sgml;, Text, ISO2709 (&marc;)</entry>
+ <entry>
+ A system of input filters driven by
+ regular expressions allows most ASCII-based
+ data formats to be easily processed.
+ &sgml;, &xml;, ISO2709 (&marc;), and raw text are also
+ supported.</entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry>Relevance ranking</entry>
+ <entry>TF-IDF like</entry>
+ <entry>Relevance-ranking of free-text queries is supported
+ using a TF-IDF like algorithm.</entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry>Document storage</entry>
+ <entry>Index-only, Key storage, Document storage</entry>
+ <entry>Data can be, and usually is, imported
+ into &zebra;'s own storage, but &zebra; can also refer to
+ external files, building and maintaining indexes of "live"
+ collections.</entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry>Regular expression matching</entry>
+ <entry>Regexp </entry>
+ <entry>Full regular expression matching and "approximate
+ matching" (eg. spelling mistake corrections) are handled.</entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry>Search truncation</entry>
+ <entry></entry>
+ <entry></entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry>Remote update</entry>
+ <entry>&z3950; extended services</entry>
+ <entry></entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry>Supported Platforms</entry>
+ <entry>UNIX, Linux, Windows (NT/2000/2003/XP)</entry>
+ <entry>&zebra; is written in portable C, so it runs on most
+ Unix-like systems as well as Windows (NT/2000/2003/XP). Binary
+ distributions are
+ available for GNU/Debian Linux and Windows</entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry>&z3950;</entry>
+ <entry>&z3950; protocol support</entry>
+ <entry> Protocol facilities: Init, Search, Present (retrieval),
+ Segmentation (support for very large records), Delete, Scan
+ (index browsing), Sort, Close and support for the ``update''
+ Extended Service to add or replace an existing &xml;
+ record. Piggy-backed presents are honored in the search
+ request. Named result sets are supported.</entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry>Record Syntaxes</entry>
+ <entry></entry>
+ <entry> Multiple record syntaxes
+ for data retrieval: &grs1;, &sutrs;,
+ &xml;, ISO2709 (&marc;), etc. Records can be mapped between record syntaxes
+ and schemas on the fly.</entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry>Web Service support</entry>
+ <entry>&sru_gps;</entry>
+ <entry> The protocol operations <literal>explain</literal>,
+ <literal>searchRetrieve</literal> and <literal>scan</literal>
+ are supported. <ulink url="&url.cql;">&cql;</ulink> to internal
+ query model &rpn; conversion is supported. Extended RPN queries
+ for search/retrieve and scan are supported.</entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry></entry>
+ <entry></entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry></entry>
+ <entry></entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry></entry>
+ <entry></entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry></entry>
+ <entry></entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry></entry>
+ <entry></entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry></entry>
+ <entry></entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry></entry>
+ <entry></entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry></entry>
+ <entry></entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry></entry>
+ <entry></entry>
+ <entry><xref linkend=""/></entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+
+