Data Control Language
As database security administrator, you use Data Control Language (DCL) SQL commands to control user access to database objects and their contents.
Security starts with the admin user. As the admin user, you must create and authorize other users. When you first create users, they cannot see or do anything. As you grant users more privileges, they can access more database objects.
When you create users, by default they have access only to system views. With these views, they can retrieve lists of user database objects and select data within those objects. Because security is also built into these system views, the list of database objects a user can see depends on the security privileges of the user.
The following table describes the DCL.