Table with contacts: how to differ between people and organizations?

In several projects, I've seen the same problem pop up. But so far, I have not found a satisfying solution. Here's the issue. I need a table with contacts. These 'contacts' could be individual people, or organizations. From one point of view, I prefer to have these contacts mixed (one table with both types), but from another point of view, I prefer to have them separated. Here's some arguments:

• A company that sells products to the general public has 'clients' of both types. When relating a sale, it is most convenient to refer to a 'client ID' without having to specify what type of client this is (for each sale).

• A company can have many providers that it uses. Some are individual people (like a plummer or a consultant), others are companies. When relating a 'purchase order' I again prefer to relate to just one provider ID, without having to differentiate between provider types.

• When managing the actual contacts, I do want to differentiate between the two types. That way, I can have the right fields for each. For instance, "First Name" and "Last Name" are not useful for companies, but they do are for people. Also, if I have a separate table, I can actually link people working at specific organizations.

Being pretty common - I guess - I hope that others have tackled this problem before. What is the way you set this up?

I suggest you create them as separate tables.

-
Create an Individuals table and an Organizations table so that each
can have the proper fields for their respective types.

-
Draw from the same sequence to populate the ClientID field in both
tables.

-
Create a view to UNION ALL both tables for code that needs
information about both.

-
Create foreign keys to the tables as necessary.

StackExchange Database Administrators Q#17807, answer score: 2