I use a recursive table to implement a hierarchical structure in SQL and the Zope tree tag to display it. This works perfect with Zope 2.0.1 recently I upgraded to 2.1.6. Since then it does not work correct. What did I do wrong and what can I do to correct the problem? thanks in advance phil Here the exact description of what I did: 1. SQL statement: ---------------------- create table Item(ItemId int,parentID int,name varchar(30)) 2. In Zope I defined a SQL Method called 'Item' with an argument called 'parentID': ---------------------------------------------------------------- select * from Item where parentID=<dtml-var parentID> 3. I defined a DTML document to display the tree: --------------------------------------------------------------------- <!--#var standard_html_header--> <dtml-let ItemID="-1"> <dtml-tree id=ItemID branches_expr="Item(parentID=ItemID)"> <dtml-var name> </a> <br> </dtml-tree> </dtml-let> <!--#var standard_html_footer--> ---------------------------------- Under Zope 2.0.1 the tree displays correct: world europe austria belgium denmark france germany italy netherla switzerl northamerica Under Zope 2.1.6 exact the same code displays like this: world europe europe europe europe europe europe northamerica northamerica northamerica northamerica northamerica northamerica