1. Do what you have now.
2. Have the separate relation table PIEBALD suggested.
3. Have a special warehouse, a real entry in the database, however it corresponds to "no warehouse" with values (stock, staff count, ...) that match that (probably just all zero, and a dummy address).
If you are strictly modelling what's in the database, then I would simplify this by making it so that Warehouse1 and Warehouse2 were nullable, and I would let getWarehouseModel return null if the warehouse id was null. Also, are you sure that your logic for getWarehouseModel is correct with regards to what you are evaluating? You seem to be using WarehouseId1 in both cases and it seems redundant evaluating it twice.
Before you can actually progress with this project, you really need to flesh out your requirements. What employee information do you need? Do you require security in place? How are you going to present this to the user? Is it browser based? Is it Silverlight, Windows Forms, WPF? Do you need to audit changes?
As you can see, there's a lot that you need to do before you go any further.
I don't think anyone here is furious - if they had been the tone of the messages you got would have been very different, I think.
But, most of us here have worked hard to get where we are, and we know that doing your homework would not help us and would not help you. All it would do is reinforce the idea you seem to have that "deadlines are for other people" and that someone will drag your backside out of the fire if you can't be bothered to plan your time.
Unfortunately, the real world is not like that.
Ideological Purity is no substitute for being able to stick your thumb down a pipe to stop the water
I don't think everybody is furious. The tone would be far nastier if they were. What you have to understand, though, is that your original statement was far too vague, and far too broad. We don't know what technology (other than C#) you are using, and we don't know what you've done so far - it's up to you to help us help you.
Im trying to insert cross reference into a word document, the document itself is consists of 2 headings:
while trying to iterate through all the subjects with GetCrossReferenceItems(ref oRefType); function I do get both of the subjects, however, when I use the InsertCrossReference function, it always inserts the last subject into the document (meaning, I get duplicate SUBJECT2 cross references)
See below simplified example: