<chapter id="examples">
- <!-- $Id: examples.xml,v 1.17 2002-11-08 17:00:57 mike Exp $ -->
+ <!-- $Id: examples.xml,v 1.27 2007-05-24 13:44:09 adam Exp $ -->
<title>Example Configurations</title>
- <sect1>
+ <sect1 id="examples-overview">
<title>Overview</title>
<para>
- <literal>zebraidx</literal> and <literal>zebrasrv</literal> are both
+ <command>zebraidx</command> and
+ <command>zebrasrv</command> are both
driven by a master configuration file, which may refer to other
subsidiary configuration files. By default, they try to use
<filename>zebra.cfg</filename> in the working directory as the
option to specify an alternative master configuration file.
</para>
<para>
- The master configuration file tells Zebra:
+ The master configuration file tells &zebra;:
<itemizedlist>
<listitem>
<para>
- Where to find subsidiary configuration files, including
- <literal>default.idx</literal>
+ Where to find subsidiary configuration files, including both
+ those that are named explicitly and a few ``magic'' files such
+ as <literal>default.idx</literal>,
which specifies the default indexing rules.
</para>
</listitem>
<listitem>
<para>
- What attribute sets to recognise in searches.
+ What record schemas to support. (Subsidiary files specifiy how
+ to index the contents of records in those schemas, and what
+ format to use when presenting records in those schemas to client
+ software.)
</para>
</listitem>
<listitem>
<para>
- Policy details such as what record type to expect, what
- low-level indexing algorithm to use, how to identify potential
- duplicate records, etc.
+ What attribute sets to recognise in searches. (Subsidiary files
+ specify how to interpret the attributes in terms
+ of the indexes that are created on the records.)
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ Policy details such as what type of input format to expect when
+ adding new records, what low-level indexing algorithm to use,
+ how to identify potential duplicate records, etc.
</para>
</listitem>
</sect1>
<sect1 id="example1">
- <title>Example 1: XML Indexing And Searching</title>
+ <title>Example 1: &acro.xml; Indexing And Searching</title>
<para>
- This example shows how Zebra can be used with absolutely minimal
+ This example shows how &zebra; can be used with absolutely minimal
configuration to index a body of
- <ulink url="http://www.w3.org/XML/">XML</ulink>
+ <ulink url="&url.xml;">&acro.xml;</ulink>
documents, and search them using
- <ulink url="http://www.w3.org/TR/xpath">XPath</ulink>
+ <ulink url="&url.xpath;">XPath</ulink>
expressions to specify access points.
</para>
<para>
records are generated from the family tree in the file
<literal>dino.tree</literal>.)
Type <literal>make records/dino.xml</literal>
- to make the XML data file.
+ to make the &acro.xml; data file.
+ (Or you could just type <literal>make dino</literal> to build the &acro.xml;
+ data file, create the database and populate it with the taxonomic
+ records all in one shot - but then you wouldn't learn anything,
+ would you? :-)
</para>
<para>
- Now we need to create a Zebra database to hold and index the XML
+ Now we need to create a &zebra; database to hold and index the &acro.xml;
records. We do this with the
- Zebra indexer, <literal>zebraidx</literal>, which is
+ &zebra; indexer, <command>zebraidx</command>, which is
driven by the <literal>zebra.cfg</literal> configuration file.
For our purposes, we don't need any
- special behaviour - we can use the defaults - so we start with a
- minimal file that just tells <literal>zebraidx</literal> where to
+ special behaviour - we can use the defaults - so we can start with a
+ minimal file that just tells <command>zebraidx</command> where to
find the default indexing rules, and how to parse the records:
<screen>
profilePath: .:../../tab
</screen>
</para>
<para>
- That's all you need for a minimal Zebra configuration. Now you can
- roll the XML records into the database and build the indexes:
+ That's all you need for a minimal &zebra; configuration. Now you can
+ roll the &acro.xml; records into the database and build the indexes:
<screen>
zebraidx update records
</screen>
<xref linkend="zebrasrv"/>.
</para>
<para>
- Now you can use the Z39.50 client program of your choice to execute
- XPath-based boolean queries and fetch the XML records that satisfy
+ Now you can use the &acro.z3950; client program of your choice to execute
+ XPath-based boolean queries and fetch the &acro.xml; records that satisfy
them:
<screen>
- $ yaz-client tcp:@:9999
+ $ yaz-client @:9999
Connecting...Ok.
Z> find @attr 1=/Zthes/termName Sauroposeidon
Number of hits: 1
<termId>22</termId>
<termName>Sauroposeidon</termName>
<termType>PT</termType>
+ <termNote>The tallest known dinosaur (18m)</termNote>
<relation>
<relationType>BT</relationType>
<termId>21</termId>
</relation>
<idzebra xmlns="http://www.indexdata.dk/zebra/">
- <size>245</size>
+ <size>300</size>
<localnumber>23</localnumber>
<filename>records/dino.xml</filename>
</idzebra>
</screen>
</para>
<para>
- Now wasn't that easy?
+ Now wasn't that nice and easy?
</para>
</sect1>
significantly because it ties searching semantics to the physical
structure of the searched records. You can't use the same search
specification to search two databases if their internal
- representations are different. Consider an alternative taxonomy
+ representations are different. Consider a different taxonomy
database in which the records have taxon names specified
inside a <literal><name></literal> element nested within a
<literal><identification></literal> element
<para>
How, then, can we build broadcasting Information Retrieval
applications that look for records in many different databases?
- The Z39.50 protocol offers a powerful and general solution to this:
- abstract ``access points''. In the Z39.50 model, an access point
+ The &acro.z3950; protocol offers a powerful and general solution to this:
+ abstract ``access points''. In the &acro.z3950; model, an access point
is simply a point at which searches can be directed. Nothing is
said about implementation: in a given database, an access point
might be implemented as an index, a path into physical records, an
algorithm for interrogating relational tables or whatever works.
- The key point is that the semantics of an access point are fixed
- and well defined.
+ The only important thing is that the semantics of an access
+ point is fixed and well defined.
</para>
<para>
For convenience, access points are gathered into <firstterm>attribute
- sets</firstterm>. For example, the BIB-1 attribute set is supposed to
+ sets</firstterm>. For example, the &acro.bib1; attribute set is supposed to
contain bibliographic access points such as author, title, subject
and ISBN; the GEO attribute set contains access points pertaining
to geospatial information (bounding coordinates, stratum, latitude
(provenance, inscriptions, etc.)
</para>
<para>
- In practice, the BIB-1 attribute set has tended to be a dumping
+ In practice, the &acro.bib1; attribute set has tended to be a dumping
ground for all sorts of access points, so that, for example, it
includes some geospatial access points as well as strictly
- bibliographic ones. Nevertheless, the key point is that this model
+ bibliographic ones. Nevertheless, this model
allows a layer of abstraction over the physical representation of
records in databases.
</para>
<para>
- In the BIB-1 attribute set, a taxon name is probably best
+ In the &acro.bib1; attribute set, a taxon name is probably best
interpreted as a title - that is, a phrase that identifies the item
- in question. BIB-1 represents title searches by
- access point 4. (See
- <ulink url="ftp://ftp.loc.gov/pub/z3950/defs/bib1.txt"
- >The BIB-1 Attribute Set Semantics</ulink>)
+ in question. &acro.bib1; represents title searches by
+ access point 4. (See
+ <ulink url="&url.z39.50.bib1.semantics;">The &acro.bib1; Attribute
+ Set Semantics</ulink>)
So we need to configure our dinosaur database so that searches for
- BIB-1 access point 4 look in the
+ &acro.bib1; access point 4 look in the
<literal><termName></literal> element,
inside the top-level
<literal><Zthes></literal> element.
</para>
<para>
- This is a two-step process. First, we need to tell Zebra that we
- want to support the BIB-1 attribute set. Then we need to tell it
+ This is a two-step process. First, we need to tell &zebra; that we
+ want to support the &acro.bib1; attribute set. Then we need to tell it
which elements of its record pertain to access point 4.
- </para>
- <para>
+ </para>
+ <para>
We need to create an <link linkend="abs-file">Abstract Syntax
file</link> named after the document element of the records we're
- working with, plus a <literal>.abs</literal> suffix - in this case,
- <literal>Zthes.abs</literal> - as follows:
- </para>
- <itemizedlist>
- <listitem>
- <para>
-
- </para>
- </listitem>
- <listitem>
- <para>
- </para>
- </listitem>
- </itemizedlist>
+ working with, plus a <literal>.abs</literal> suffix - in this case,
+ <literal>Zthes.abs</literal> - as follows:
+ </para>
+ <programlistingco>
+ <areaspec>
+ <area id="attset.zthes" coords="2"/>
+ <area id="attset.attset" coords="3"/>
+ <area id="termId" coords="7"/>
+ <area id="termName" coords="8"/>
+ </areaspec>
+ <programlisting>
+attset zthes.att
+attset bib1.att
+xpath enable
+systag sysno none
+
+xelm /Zthes/termId termId:w
+xelm /Zthes/termName termName:w,title:w
+xelm /Zthes/termQualifier termQualifier:w
+xelm /Zthes/termType termType:w
+xelm /Zthes/termLanguage termLanguage:w
+xelm /Zthes/termNote termNote:w
+xelm /Zthes/termCreatedDate termCreatedDate:w
+xelm /Zthes/termCreatedBy termCreatedBy:w
+xelm /Zthes/termModifiedDate termModifiedDate:w
+xelm /Zthes/termModifiedBy termModifiedBy:w
+ </programlisting>
+ <calloutlist>
+ <callout arearefs="attset.zthes">
+ <para>
+ Declare Thesausus attribute set. See <filename>zthes.att</filename>.
+ </para>
+ </callout>
+ <callout arearefs="attset.attset">
+ <para>
+ Declare &acro.bib1; attribute set. See <filename>bib1.att</filename> in
+ &zebra;'s <filename>tab</filename> directory.
+ </para>
+ </callout>
+ <callout arearefs="termId">
+ <para>
+ This xelm directive selects contents of nodes by XPath expression
+ <literal>/Zthes/termId</literal>. The contents (CDATA) will be
+ word searchable by Zthes attribute termId (value 1001).
+ </para>
+ </callout>
+ <callout arearefs="termName">
+ <para>
+ Make <literal>termName</literal> word searchable by both
+ Zthes attribute termName (1002) and &acro.bib1; atttribute title (4).
+ </para>
+ </callout>
+ </calloutlist>
+ </programlistingco>
+ <para>
+ After re-indexing, we can search the database using &acro.bib1;
+ attribute, title, as follows:
+ <screen>
+Z> form xml
+Z> f @attr 1=4 Eoraptor
+Sent searchRequest.
+Received SearchResponse.
+Search was a success.
+Number of hits: 1, setno 1
+SearchResult-1: Eoraptor(1)
+records returned: 0
+Elapsed: 0.106896
+Z> s
+Sent presentRequest (1+1).
+Records: 1
+[Default]Record type: &acro.xml;
+<Zthes>
+ <termId>2</termId>
+ <termName>Eoraptor</termName>
+ <termType>PT</termType>
+ <termNote>The most basal known dinosaur</termNote>
+ ...
+ </screen>
+ </para>
</sect1>
</chapter>
by exporting a line-drawing done in TGIF, then converted that to the
GIF using a shell-script called "epstogif" which used an appallingly
baroque sequence of conversions, which I would prefer not to pollute
-the Zebra build environment with:
+the &zebra; build environment with:
#!/bin/sh