Index: openacs-4/packages/acs-core-docs/www/xml/developers-guide/tutorial-advanced.xml
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-core-docs/www/xml/developers-guide/tutorial-advanced.xml,v
diff -u -r1.4.2.9 -r1.4.2.10
--- openacs-4/packages/acs-core-docs/www/xml/developers-guide/tutorial-advanced.xml	10 Feb 2004 13:18:28 -0000	1.4.2.9
+++ openacs-4/packages/acs-core-docs/www/xml/developers-guide/tutorial-advanced.xml	19 Feb 2004 18:17:00 -0000	1.4.2.10
@@ -577,7 +577,13 @@
     <para>One of the nice things about using the OpenACS object system
     is that it has a built-in facility for tracking hierarchical data
     in an efficient way. The algorithm behind this is called
-    <computeroutput>tree_sortkey.</computeroutput></para>
+    <computeroutput>tree_sortkey.</computeroutput>. This is built into
+    the PostgreSql portion of the
+    <computeroutput>acs_objects</computeroutput> table. (If you are
+    using Oracle, then you should just use CONNECT BY to build your
+    hierarchical queries, using context_id as the parent_id
+    column). Note that packages based on acs_objects use and/or abuse
+    context_id inconsistently to maintain a hierarchy.</para>
 
     <para>Any time your tables are subclasses of the acs_objects
     table, then you automatically get the ability to structure them