Index: openacs-4/packages/categories/www/doc/design.html
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/categories/www/doc/design.html,v
diff -u -r1.1 -r1.2
--- openacs-4/packages/categories/www/doc/design.html	18 Jan 2004 16:32:55 -0000	1.1
+++ openacs-4/packages/categories/www/doc/design.html	12 Jul 2004 14:49:55 -0000	1.2
@@ -123,7 +123,11 @@
 
 <p>
 This table stores the tree hierarchy by holding the information about
-the parent category. The tree is ordered by a nested index (left_ind, right_ind).
+the parent category. The tree is ordered by a nested index (left_ind,
+right_ind). Sorting is thus accomplished by means of a nested set. You 
+can read a <a href="http://www.intelligententerprise.com/001020/celko.jhtml?_requestid=49180">description of how nested sets work</a>. This also <i>describes how to write queries that sort correctly when using categories</i>.
+
+
 <pre>
 create table categories (
        category_id		    integer primary key