Is this a good way to model address information in a relational database?

Question

I\'m wondering if this is a good design. I have a number of tables that require address information (e.g. street, post code/zip, country, fax, email). Sometimes the same a

Answer 1

I actually use this as one of my interview questions. The following is a good place to start:

Addresses
---------
AddressId (PK)
Street1
... (etc)

and

AddressTypes
------------
AddressTypeId
AddressTypeName

and

UserAddresses (substitute "Company", "Account", whatever for Users)
-------------
UserId
AddressTypeId
AddressId

This way, your addresses are totally unaware of how they are being used, and your entities (Users, Accounts) don't directly know anything about addresses either. It's all up to the linking tables you create (UserAddresses in this case, but you can do whatever fits your model).

One piece of somewhat contradictory advice for a potentially large database: go ahead and put a "primary" address directly on your entities (in the Users table in this case) along with a "HasMoreAddresses" field. It seems icky compared to just using the clean design above, but can simplify coding for typical use cases, and the denormalization can make a big difference for performance.