<chapter id="server">
- <!-- $Id: server.xml,v 1.22 2006-06-07 13:17:48 marc Exp $ -->
+ <!-- $Id: server.xml,v 1.23 2006-06-13 09:27:01 marc Exp $ -->
<title>The Z39.50 Server</title>
<sect1 id="zebrasrv">
also the following section).
</para>
- <para>
- <emphasis>Use</emphasis> attributes are interpreted according to the
- attribute sets which have been loaded in the
- <literal>zebra.cfg</literal> file, and are matched against specific
- fields as specified in the <literal>.abs</literal> file which
- describes the profile of the records which have been loaded.
- If no Use attribute is provided, a default of Bib-1 Any is assumed.
- </para>
-
- <para>
- If a <emphasis>Structure</emphasis> attribute of
- <emphasis>Phrase</emphasis> is used in conjunction with a
- <emphasis>Completeness</emphasis> attribute of
- <emphasis>Complete (Sub)field</emphasis>, the term is matched
- against the contents of the phrase (long word) register, if one
- exists for the given <emphasis>Use</emphasis> attribute.
- A phrase register is created for those fields in the
- <literal>.abs</literal> file that contains a
- <literal>p</literal>-specifier.
- <!-- ### whatever the hell _that_ is -->
- </para>
-
- <para>
- If <emphasis>Structure</emphasis>=<emphasis>Phrase</emphasis> is
- used in conjunction with <emphasis>Incomplete Field</emphasis> - the
- default value for <emphasis>Completeness</emphasis>, the
- search is directed against the normal word registers, but if the term
- contains multiple words, the term will only match if all of the words
- are found immediately adjacent, and in the given order.
- The word search is performed on those fields that are indexed as
- type <literal>w</literal> in the <literal>.abs</literal> file.
- </para>
-
- <para>
- If the <emphasis>Structure</emphasis> attribute is
- <emphasis>Word List</emphasis>,
- <emphasis>Free-form Text</emphasis>, or
- <emphasis>Document Text</emphasis>, the term is treated as a
- natural-language, relevance-ranked query.
- This search type uses the word register, i.e. those fields
- that are indexed as type <literal>w</literal> in the
- <literal>.abs</literal> file.
- </para>
-
- <para>
- If the <emphasis>Structure</emphasis> attribute is
- <emphasis>Numeric String</emphasis> the term is treated as an integer.
- The search is performed on those fields that are indexed
- as type <literal>n</literal> in the <literal>.abs</literal> file.
- </para>
-
- <para>
- If the <emphasis>Structure</emphasis> attribute is
- <emphasis>URx</emphasis> the term is treated as a URX (URL) entity.
- The search is performed on those fields that are indexed as type
- <literal>u</literal> in the <literal>.abs</literal> file.
- </para>
-
- <para>
- If the <emphasis>Structure</emphasis> attribute is
- <emphasis>Local Number</emphasis> the term is treated as
- native Zebra Record Identifier.
- </para>
-
- <para>
- If the <emphasis>Relation</emphasis> attribute is
- <emphasis>Equals</emphasis> (default), the term is matched
- in a normal fashion (modulo truncation and processing of
- individual words, if required).
- If <emphasis>Relation</emphasis> is <emphasis>Less Than</emphasis>,
- <emphasis>Less Than or Equal</emphasis>,
- <emphasis>Greater than</emphasis>, or <emphasis>Greater than or
- Equal</emphasis>, the term is assumed to be numerical, and a
- standard regular expression is constructed to match the given
- expression.
- If <emphasis>Relation</emphasis> is <emphasis>Relevance</emphasis>,
- the standard natural-language query processor is invoked.
- </para>
-
- <para>
- For the <emphasis>Truncation</emphasis> attribute,
- <emphasis>No Truncation</emphasis> is the default.
- <emphasis>Left Truncation</emphasis> is not supported.
- <emphasis>Process # in search term</emphasis> is supported, as is
- <emphasis>Regxp-1</emphasis>.
- <emphasis>Regxp-2</emphasis> enables the fault-tolerant (fuzzy)
- search. As a default, a single error (deletion, insertion,
- replacement) is accepted when terms are matched against the register
- contents.
- </para>
-
- <sect3>
- <title>Regular expressions</title>
-
- <para>
- Each term in a query is interpreted as a regular expression if
- the truncation value is either <emphasis>Regxp-1</emphasis> (102)
- or <emphasis>Regxp-2</emphasis> (103).
- Both query types follow the same syntax with the operands:
- <variablelist>
-
- <varlistentry>
- <term>x</term>
- <listitem>
- <para>
- Matches the character <emphasis>x</emphasis>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>.</term>
- <listitem>
- <para>
- Matches any character.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><literal>[</literal>..<literal>]</literal></term>
- <listitem>
- <para>
- Matches the set of characters specified;
- such as <literal>[abc]</literal> or <literal>[a-c]</literal>.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- and the operators:
- <variablelist>
-
- <varlistentry>
- <term>x*</term>
- <listitem>
- <para>
- Matches <emphasis>x</emphasis> zero or more times. Priority: high.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>x+</term>
- <listitem>
- <para>
- Matches <emphasis>x</emphasis> one or more times. Priority: high.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>x?</term>
- <listitem>
- <para>
- Matches <emphasis>x</emphasis> zero or once. Priority: high.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>xy</term>
- <listitem>
- <para>
- Matches <emphasis>x</emphasis>, then <emphasis>y</emphasis>.
- Priority: medium.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>x|y</term>
- <listitem>
- <para>
- Matches either <emphasis>x</emphasis> or <emphasis>y</emphasis>.
- Priority: low.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- The order of evaluation may be changed by using parentheses.
- </para>
-
- <para>
- If the first character of the <emphasis>Regxp-2</emphasis> query
- is a plus character (<literal>+</literal>) it marks the
- beginning of a section with non-standard specifiers.
- The next plus character marks the end of the section.
- Currently Zebra only supports one specifier, the error tolerance,
- which consists one digit.
- </para>
-
- <para>
- Since the plus operator is normally a suffix operator the addition to
- the query syntax doesn't violate the syntax for standard regular
- expressions.
- </para>
-
- </sect3>
-
- <sect3>
- <title>Query examples</title>
-
- <para>
- Phrase search for <emphasis>information retrieval</emphasis> in
- the title-register:
- <screen>
- @attr 1=4 "information retrieval"
- </screen>
- </para>
-
- <para>
- Ranked search for the same thing:
- <screen>
- @attr 1=4 @attr 2=102 "Information retrieval"
- </screen>
- </para>
-
- <para>
- Phrase search with a regular expression:
- <screen>
- @attr 1=4 @attr 5=102 "informat.* retrieval"
- </screen>
- </para>
-
- <para>
- Ranked search with a regular expression:
- <screen>
- @attr 1=4 @attr 5=102 @attr 2=102 "informat.* retrieval"
- </screen>
- </para>
-
- <para>
- In the GILS schema (<literal>gils.abs</literal>), the
- west-bounding-coordinate is indexed as type <literal>n</literal>,
- and is therefore searched by specifying
- <emphasis>structure</emphasis>=<emphasis>Numeric String</emphasis>.
- To match all those records with west-bounding-coordinate greater
- than -114 we use the following query:
- <screen>
- @attr 4=109 @attr 2=5 @attr gils 1=2038 -114
- </screen>
- </para>
- </sect3>
</sect2>
<sect2>
will not be searchable.
</para>
</note>
- <para>
- The following Explain categories are supported:
- <literal>CategoryList</literal>, <literal>TargetInfo</literal>,
- <literal>DatabaseInfo</literal>, <literal>AttributeDetails</literal>.
- </para>
- <para>
- The following Explain search atributes are supported:
- <literal>ExplainCategory</literal> (@attr 1=1),
- <literal>DatabaseName</literal> (@attr 1=3),
- <literal>DateAdded</literal> (@attr 1=9),
- <literal>DateChanged</literal>(@ayyt 1=10).
- See <filename>tab/explain.att</filename> for more information.
- </para>
-
- <sect3>
- <title>Example searches with yaz-client</title>
-
-
- <para>
- List supported categories to find out which explain commands are
- supported:
- <screen>
- Z> base IR-Explain-1
- Z> @attr exp1 1=1 categorylist
- Z> form sutrs
- Z> show 1+2
- </screen>
- </para>
-
- <para>
- Get target info, that is, investigate which databases exist at
- this server endpoint:
- <screen>
- Z> base IR-Explain-1
- Z> @attr exp1 1=1 targetinfo
- Z> form xml
- Z> show 1+1
- Z> form grs-1
- Z> show 1+1
- Z> form sutrs
- Z> show 1+1
- </screen>
- </para>
-
- <para>
- List all supported databases, the number of hits
- is the number of databases found, which most commonly are the
- following two:
- the <literal>Default</literal> and the
- <literal>IR-Explain-1</literal> databases.
- <screen>
- Z> base IR-Explain-1
- Z> f @attr exp1 1=1 databaseinfo
- Z> form sutrs
- Z> show 1+2
- </screen>
- </para>
-
- <para>
- Get database info record for database <literal>Default</literal>.
- <screen>
- Z> base IR-Explain-1
- Z> @and @attr exp1 1=1 databaseinfo @attr exp1 1=3 Default
- </screen>
- Identical query with explicitly specified attribute set:
- <screen>
- Z> base IR-Explain-1
- Z> @attrset exp1 @and @attr 1=1 databaseinfo @attr 1=3 Default
- </screen>
- </para>
-
- <para>
- Get attribute details record for database
- <literal>Default</literal>.
- This query is very useful to study the internal Zebra indexes.
- If records have been indexed using the <literal>alvis</literal>
- XSLT filter, the string representation names of the known indexes can be
- found.
- <screen>
- Z> base IR-Explain-1
- Z> @and @attr exp1 1=1 attributedetails @attr exp1 1=3 Default
- </screen>
- Identical query with explicitly specified attribute set:
- <screen>
- Z> base IR-Explain-1
- Z> @attrset exp1 @and @attr 1=1 attributedetails @attr 1=3 Default
- </screen>
- </para>
-
- </sect3>
</sect2>
</sect1>
</chapter>
projects / idzebra-moved-to-github.git / blobdiff