Help With Partitioned Views Or Updating Data From Multiple Tables

Hi All,

My database's design is set out here. In summary, I'm trying to model a Stock Exchange for a Technical Analysis application written using Visual C++. In order to create the hierachy I'm using a Nested Set Model. I'm now trying to write code to add and delete equities (or, more generically, nodes) to the database using a form presented to the user in my application. I have example SQL code to create the necessary add and delete procedures that calculate the changes to the values in the lft and rgt columns, but these examples focus around a single table, where as my design aggregates rows from multiple tables using UNION ALL:




Code Snippet
CREATE VIEW vw_NSM_DBHierarchy -- Nested Set Model Database Hierarchy
AS
SELECT clmStockExchange, clmLeft, clmRight FROM tblStockExchange_
UNION ALL
SELECT clmMarkets, clmLeft, clmRight FROM tblMarkets_
UNION ALL
SELECT clmSectors, clmLeft, clmRight FROM tblSectors_
UNION ALL
SELECT clmEPIC, clmLeft, clmRight FROM tblEquities_




Essentially, I'm trying to create an updateable view but I receive the error "UNION ALL View is not updatable because a partitioning column was not found". I suspect that my design in wrong or lacks and this problem is highlighting the design flaws so any suggestions would be greatly appreciated.