>>>>>>>Do you want to have a trigger firing when a new column is added?
>>>>>>Yes
>>>>>> In SQL Server 2005 you need to look at DDL triggers.
>>>>>>Why?
>>>>>>
>>>>>>Viv
>>>>>>
>>>>>>
>>>>>Why not? DDL triggers are supposed to fire when the structure changes - looks like your case.
>>>>No - structure doesn't change. It's just an INSERT into the ProductFileColumns table.
>>>>When that happens I need to add a record in ProductFileData for each existing row using the Id of the newly inserted column.
>>>
>>>Aha, when what seems to be a problem? Just write a simple AFTER INSERT trigger.
>>As per the original post I don't know how to do this in the most efficient way. Care to post some code?
>>Best,
>>Viv
>
>Can you post what you tried already?
>
>To me this sounds like
>
>trigger body
>
>insert into mySecondTable select ID, some other info from Inserted

This works - but requires a ProductFileId field in ProductFileData:

    DECLARE @rowid uniqueidentifier
    SET @rowid = NEWID()
    INSERT INTO ProductFileData
    (ProductFileColumnId,ProductFileRowId,ProductFileId)
    SELECT INSERTED.Id,@rowid,INSERTED.ProductFileId
    FROM INSERTED INNER JOIN ProductFileData ON ProductFileData.ProductFileId = INSERTED.ProductFileId

UPDATE: On second thoughts - it doesn't - I need unique row IDs.....