Queries :: Update Query That Ignores Missing Fields?

I'm trying to create a single, Update Query in Access 2007 that does all of these 3 things:

Update (skipping zero-length values)
Append
Automatically handle missing Fields without showing any "Enter Parameter Value" prompts.

I've managed to accomplish the 1st & 2nd items on my own, but I'm stumped on the 3rd. In essence, what I'm looking for is a way of telling Access to automatically use a zero-length/null value for any missing Field(s) the Query encounters, so long as it does not involve manually modifying the Table beforehand. Automation is key. And that's where you guys come in.

Attached, is a diagram of the desired results applied to a set of sample Tables. And here's the SQL code for the Update Query adjusted to work with those sample Tables:

Code:
UPDATE Table_1 RIGHT JOIN Table_2 ON Table_1.ID = Table_2.ID SET Table_1.ID = NZ([Table_2].[ID],[Table_1].[ID]), Table_1.Company = NZ([Table_2].[Company],[Table_1].[Company]), Table_1.Address = NZ([Table_2].[Address],[Table_1].[Address]), Table_1.Phone = NZ([Table_2].[Phone],[Table_1].[Phone]);