+--- 1.6.23 2013/01/02
+
+Extend info command with hostname and YAZ SHA1
+Indent results for both command stat and info.
+
+Allow limit on merged content. The new configuration metadata
+element, limitcluster, configures that a metadata element (name) be used
+as limit name for search. Applies to the whole service (ie all targets),
+unlike pz:limitmap which is configured per-target (database).
+
+New feature: limitmap local:* matches against all metadata fields.
+
+Allow repeated list in limitmap spec . Separated by comma. For
+example: value="local:title,rpn:@attr 1=4".
+
+New element <message> in bytarget response. Holds diagnostic message
+of code (say 'Unsupported Use Attribute' for Bib-1 114).
+
+Improved logging for record ingestion failures.
+
+Avoid using struct icu_chain in non-YAZ_HAVE_ICU mode. In the rare case,
+when YAZ is compiled without ICU support.
+
+--- 1.6.22 2012/10/11
+
+Requires YAZ-4.2.40 to support native solr support.
+
+Fix and improve logic handling whether or not to re-do search on sort
+order changes. A sort order with change in ascending/descending only
+whould not trigger a new search, which is required for targets with
+native sorting capabilities. Each client is now checked if instructions
+(sortmap) exist for native sorting and only client that does requires
+it is researched. Other clients is just re-ingesting the records,
+they already have. The resultset is now cleared if any researching
+is done.
+
+Connection sharing between session has broken since version 1.6.8 with
+introduction of logic that would minimize searching if pazpar2 could
+detect this based on same query and limits and partly sort order.
+This could lead to segementations violations.
+
+Added a chapter in the manaul about relevance ranking.
+
+--- 1.6.21 2012/09/24
Rank tweak: follow=number will increase mult by number if two terms
occur next to each other; number-1 if they are one term apart , .. 0
if they are number a part (all in order). Default is 0 (following
terms has no effect).
-Rank tweak: lead=number will increase mult by number if term is first
-term in field, number-1 if second, ... 0 if term is at offset
-number of more. Default value is 0 (position irrelevant).
+Rank tweak: lead=k will divide mult by 1 + log2(1+k*l) where k is
+value given by lead and l is length from beginning of field where
+term occurs (l=0 for first term, l=1 for second term, ..). Default
+value of k is 0.0.
Rank tweak: length=strategy. length="linear" if mult is to be divided
by length (existing, default behavior), length="log" if mult is to be
--- 1.6.20 2012/09/21
-Rank algorithm details may be printed as part of show reseponse in
+Rank algorithm details may be printed as part of show response in
element <relevance_info>.. This is only printed if <rank debug="yes"/>
is used in service.