+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>rank</term>
+ <listitem>
+ <para>
+ Specifies that this element is to be used to
+ help rank
+ records against the user's query (when ranking is
+ requested). The value is an integer, used as a
+ multiplier against the basic TF*IDF score. A value of
+ 1 is the base, higher values give additional
+ weight to
+ elements of this type. The default is '0', which
+ excludes this element from the rank calculation.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>termlist</term>
+ <listitem>
+ <para>
+ Specifies that this element is to be used as a
+ termlist, or browse facet. Values are tabulated from
+ incoming records, and a highscore of values (with
+ their associated frequency) is made available to the
+ client through the webservice API.
+ The possible values
+ are 'yes' and 'no' (default).
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>merge</term>
+ <listitem>
+ <para>
+ This governs whether, and how elements are extracted
+ from individual records and merged into cluster
+ records. The possible values are: 'unique' (include
+ all unique elements), 'longest' (include only the
+ longest element (strlen), 'range' (calculate a range
+ of values across all matching records), 'all' (include
+ all elements), or 'no' (don't merge; this is the
+ default);
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>mergekey</term>
+ <listitem>
+ <para>
+ If set to '<literal>required</literal>', the value of this
+ metadata element is appended to the resulting mergekey if
+ the metadata is present in a record instance.
+ If the metadata element is not present, the a unique mergekey
+ will be generated instead.
+ </para>
+ <para>
+ If set to '<literal>optional</literal>', the value of this
+ metadata element is appended to the resulting mergekey if the
+ the metadata is present in a record instance. If the metadata
+ is not present, it will be empty.
+ </para>
+ <para>
+ If set to '<literal>no</literal>' or the mergekey attribute is
+ omitted, the metadata will not be used in the creation of a
+ mergekey.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>setting</term>
+ <listitem>
+ <para>
+ This attribute allows you to make use of static database
+ settings in the processing of records. Three possible values
+ are allowed. 'no' is the default and doesn't do anything.
+ 'postproc' copies the value of a setting with the same name
+ into the output of the normalization stylesheet(s). 'parameter'
+ makes the value of a setting with the same name available
+ as a parameter to the normalization stylesheet, so you
+ can further process the value inside of the stylesheet, or use
+ the value to decide how to deal with other data values.
+ </para>
+ <para>
+ The purpose of using settings in this way can either be to
+ control the behavior of normalization stylesheet in a database-
+ dependent way, or to easily make database-dependent values
+ available to display-logic in your user interface, without having
+ to implement complicated interactions between the user interface
+ and your configuration system.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ </variablelist> <!-- attributes to metadata -->
+
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>relevance</term>
+ <listitem>
+ <para>
+ Specifies ICU tokenization and transformation rules
+ for tokens that are used in Pazpar2's relevance ranking.
+ The 'id' attribute is currently not used, and the 'locale'
+ attribute must be set to one of the locale strings
+ defined in ICU. The child elements listed below can be
+ in any order, except the 'index' element which logically
+ belongs to the end of the list. The stated tokenization,
+ transformation and charmapping instructions are performed
+ in order from top to bottom.
+ </para>
+ <variablelist> <!-- Level 2 -->
+ <varlistentry>
+ <term>casemap</term>
+ <listitem>
+ <para>
+ The attribute 'rule' defines the direction of the
+ per-character casemapping, allowed values are "l"
+ (lower), "u" (upper), "t" (title).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>transform</term>
+ <listitem>
+ <para>
+ Normalization and transformation of tokens follows
+ the rules defined in the 'rule' attribute. For
+ possible values we refer to the extensive ICU
+ documentation found at the
+ <ulink url="&url.icu.transform;">ICU
+ transformation</ulink> home page. Set filtering
+ principles are explained at the
+ <ulink url="&url.icu.unicode.set;">ICU set and
+ filtering</ulink> page.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>tokenize</term>
+ <listitem>
+ <para>
+ Tokenization is the only rule in the ICU chain
+ which splits one token into multiple tokens. The
+ 'rule' attribute may have the following values:
+ "s" (sentence), "l" (line-break), "w" (word), and
+ "c" (character), the later probably not being
+ very useful in a pruning Pazpar2 installation.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ <para>
+ From Pazpar2 version 1.1 the ICU wrapper from YAZ is used.
+ Refer to the <ulink url="&url.yaz.yaz-icu;">yaz-icu</ulink>
+ utility for more information.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>sort</term>
+ <listitem>
+ <para>
+ Specifies ICU tokenization and transformation rules
+ for tokens that are used in Pazpar2's sorting. The contents
+ is similar to that of <literal>relevance</literal>.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>mergekey</term>
+ <listitem>
+ <para>
+ Specifies ICU tokenization and transformation rules
+ for tokens that are used in Pazpar2's mergekey. The contents
+ is similar to that of <literal>relevance</literal>.
+ </para>
+ </listitem>
+ </varlistentry>