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 -r1.1.2.1 --- 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 7 Jul 2004 17:34:52 -0000 1.1.2.1 @@ -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