Database design

I have a rather odd request, but hopefully someone who reads this newsgroup will know what I am looking for.

I am in the process of designing a database from scratch based solely on the types of things that the customer is going to need.

Since I don't have any previous database to reference I have to come up with the sizing of attributes for each of the entities.

For example, I know that I will be dealing with an entity called a CONTACT. One of the attributes for this contact will be an address. This address can have several lines such as Suite, Street address, Room number, etc. etc. plus city, province/state, postal code, etc.

Is there any univeral standard that defines attributes such as this? I want to make my CITY attribute big enough to accomodate any possible city in the world, but I don't want to make it too large. Also, while postal codes in the U.S. are 5-digits, I know that in other countries it is typically longer than that - so I would want to accomodate the largest possible postal code. For phone numbers I know that I'll have to deal with a country code, an area code, an exchange/prefix and then the number as well as a possible extension. What I want to avoid is designing my database to only work with U.S. addresses and phone numbers.

Although I've never actually worked with EDI myself, I have heard that it has established a standard for common attributes. Is this true? If so, would this be a reasonable standard to use? Received on Wed Jan 12 2000 - 09:43:48 CST