SQL Server Database Engine: Fixed Server and Database Roles

This page from 2010, has been moved into SQL Server Books Online where it can receive more consistent updates.

For more information, see:

• Server-Level Roles: /sql/relational-databases/security/authentication-access/server-level-roles 
• Database-Level Roles: https://docs.microsoft.com/sql/relational-databases/security/authentication-access/database-level-roles