Update information on target selection within the library.

diff --git a/doc/library-configuration.txt b/doc/library-configuration.txt
index 7abcfc0..3b061aa 100644 (file)
--- a/doc/library-configuration.txt
+++ b/doc/library-configuration.txt
@@ -2,26 +2,42 @@ MKWS Target Selection
 =====================
 
 
+MKWS accesses targets using the Pazpar2 metasearching engine, almost
+always fronted by the Service Proxy to manage target selection. This
+document assumes the SP is used, and so that a library of targets is
+available, maintained using an instance of MKAdmin (often
+http://mkc-admin.indexdata.com/console/)
+
+
 1. Selecting targets within the library
 ---------------------------------------
 
-MKWS applications can choose what subset of the available targets to
+MKWS applications can choose what subset of the library's targets to
 use, by means of several alternative settings on individual widgets or
 in the mkws_config structure:
 
 * targets -- contains a Pazpar2 targets string, typically of the form
   "pz:id=" or "pz:id~" followed by a pipe-separated list of low-level
-  target IDs. At present, these IDs are based on ZURLs, so a typical
-  value would be something like:
-       pz:id~josiah.brown.edu:210/innopac|connect.indexdata.com:9000/mit_opencourseware'
+  target IDs.
+
+  At present, these IDs can take one of two forms, depending on the
+  configuration of the Service Proxy being used: they may be based on
+  ZURLs, so a typical value would be something like:
+       pz:id=josiah.brown.edu:210/innopac|lui.indexdata.com:8080/solr4/select?fq=database:4902
+  Or they may be UDBs, so a typical value would be something like:
+       pz:id=brown|artstor
 
 * targetfilter -- contains a CQL query which is used to find relevant
   targets from the relvant library. For example,
        udb==Google_Images
+  Or
+       categories=news
 
 * target -- contains a single UDB, that of the sole target to be
   used. For example
        Google_Images
+  This is merely syntactic sugar for "targetfilter" with the query
+       udb==NAME
 
 
 2. Changing the library