There is a date in the error cost table, but also a PK identity column, which as I mentioned earlier is FK in the error table.

So to get the error...

I´ll try make a better explanation!

The error cost indeed does have a one-to-one relationship with the error row. The error table has a FK from the error cost table, which...

An order always appears only once in the PurchaseOrderHeader table.

If the order had 4 errors, it could actually appear in the error table (PurchaseOrderInput)

anywhere between 1 to 4 times, depending...

Why all the multiplying in the calculation? Do you have multiples of the same error?

I'm used to seeing stuff like this turned into a flat query and then Sum()...

Thanks for you advice, really appreciate it!

If this is a bad idea, please tell me why! I said I´m pretty much a beginner!

Hello and thanks for your input!

The Order/OrderDetails model doesn´t really apply in my case.

This database will be used to keep record of problems regarding purchase order intakes.

Since one purchase order...

Finally solved it by setting an "Application name" for my destination table connection manager.

In the trigger, I then check which application fired the trigger, like so:

IF (SELECT PROGRAM_NAME FROM MASTER.DBO.SYSPROCESSES...

What you guys describe is exactly what I´ve already done.

Problem is, what happens if an external application makes an update while my package is running and the trigger is disabled?...