The distinctions among Windows user permissions and any set of SQL Server GRANTs seem like unrelated concepts. As often as not, it seems to actually be implemented with pseu
Disregarding the grant table/etc side of things, the login side of things is very useful, because your app can connect to SQL server using windows authentication, which means
You don't have to put your database username and password in a file in your application somewhere
Any time you put a password in a plain text file, that's a security risk. Avoiding that is great.