There are several approaches to multi-tenant databases. For discussion, they’re usually broken into three categories.
- One database per tenant.
- Shared database, one schema per
tenant. - Shared database, shared schema. A tenant identifier (tenant key) associates every row with the right tenant.
MSDN has a good article on the pros and cons of each design, and examples of implementations.
Microsoft has apparently taken down the pages I referred to, but they are on on archive.org. Links have been changed to point there.
For reference, this is the original link for the second article