+ <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> Z39.50/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 GRS-1 Documents</entry>
+ <entry>Both XML and GRS-1 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''