I've created a SQL Login on a SQL 2005 server.
In the User Mapping tree, in the "Users mapped to this login" I select the databases that the SQL Login will be able to access. For every database that I tick the system automatically puts a tick in the PUBLIC checkbox under "database role membership for: database_name"
1. Does this mean that SQL Login now has Read-Only access to database_name?
2. I make no other adjustments. Why is it I am able to use a vendor's front-end application, together with that SQL login created earlier, to modify data in tables, etc?