responding to myself here, for posterity's sake... It turns out I _was_ on the right track... my ZClass needed to inherit from both DataSkin and from ZFolder. But, for some reason, if I put ZFolder BEFORE DataSkin in the superclass list, then I get the error I mentioned below. If, however, I put DataSkin before ZFolder, I can add my ZClasses exactly as I would expect. Once I overcame this hurdle, then the pieces fell together. I created a "Folder w/ Customizer Support". Then I created a Customizer in this folder, and I linked it to my new object type. I added a ZSQL Method to the Customizer to extract the data that I wanted from the db, and then I added a SkinScript in the Customizer's "Data Plug-Ins" tab to expose this data. Now I can add DTML Methods in my ZClass that refer to these attributes and the correct data (from the SQL database) is being displayed. Hooray! hope-it-helps-someone-else-down-the-road'ly yours, -r ra@burningman.com wrote:

Hi all,

I'm trying to create a Folder-ish ZClass that has certain attributes which are actually linked to data that lives in a SQL database. I know I could just use methods to access the data, but I'm trying to gain some ZPatterns foo, and it seems to me that I should be able to get this data to be exposed exactly as though it were just a regular attribute on a PropertySheet. I'm having a hard time finding the magic combination, though...

As I understand ZPatterns, these folder objects should be DataSkins, with DataManagers that would fetch and store the data where appropriate. However, if I try to create a ZClass with both OFS:Folder and ZPatterns:DataSkin as base classes, whenever I try to add it somewhere I get a Key Error for "_v_dm_".

Can anyone help me discover the "right" way to use ZPatterns to make a persistent Object File System type of object transparently mingle attributes from PropertySheets, SQL Methods, etc.? I know that I'm close... I just can't quite wrap my head around it...

Thanks,

-r