Building a Contact Database - Need a little schema inspiration

Microsoft offers a number of starter databases schemas, including Assets Maintenance, Contact Management, Customers and Orders, Document Management, e-Commerce, Help Desk, Issue Tracking Software, Retail Inventory Control, and Product Catalogs. See Starter Database Schemas.

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EDIT (April 2016): It appear the Microsoft webmaster broke the link. Here's the Wayback Machine archive of the page.

This is just to help with your second question; where phone extension actually belongs to relationship between person and company entities.

It's a bit trite, but you need to know your data and what you're going to do with it before you start thinking tables.

I'd suggest looking at Object Role Modeling (or this too) to define the model in plain English before you actually implement any tables. I use this VS plugin: NORMA that will also generate a schema for you too.

Alternatively, there are a bunch of data models here that may inspire you. This is "Contact Management" but there are others, such as the "Customers" section

(I just wanted to post an image..)
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