Common one-to-many table for multiple entities

Question

Suppose I have two tables, Customer and Vendor. I want to have a common address table for customer and vendor addresses. Customers and Vendors can both have one to many ad

Answer 1

can you redesign the table to have the following fields:

 Address_Type  (a flag to say that this is a customer, or a vendor)
 ID            (a common ID for both customer and vendor and depending on the flag you know what ID it is)
 Address       (Data of address itself)

or you can have two tables:

• Address table, where no reference to types of address it is. i.e. to have both
  • entity ID (key)
  • Address
• address type table, where it would point at entry and have the flag outside the table to have:
  • entity ID (FK to entity ID in the above table)
  • entity type (customer or vendor)