5.15. ROLE
A role is a database object that packages a set of SQL privileges. Roles implement the concept of access control at a group level. Multiple privileges are granted to the role and then that role can be granted to or revoked from one or many users.
A user that is granted a role must supply that role in his login credentials in order to exercise the associated privileges. Any other privileges granted to the user are not affected by his login with the role. Logging in with multiple roles simultaneously is not supported.
In this section the tasks of creating and dropping roles are discussed.
5.15.1. CREATE ROLE
Used for
Creating a new ROLE
object
Available in
DSQL, ESQL
Syntax
CREATE ROLE rolename
Parameter | Description |
---|---|
rolename | Role name. The maximum length is 31 characters |
The statement CREATE ROLE
creates a new role object, to which one or more privileges can be granted subsequently. The name of a role must be unique among the names of roles in the current database.
It is advisable to make the name of a role unique among user names as well. The system will not prevent the creation of a role whose name clashes with an existing user name but, if it happens, the user will be unable to connect to the database. |
Any user connected to the database can create a role. The user that creates a role becomes its owner.
Example
Creating a role named SELLERS
:
CREATE ROLE SELLERS;
See also
5.15.2. ALTER ROLE
ALTER ROLE
has no place in the create-alter-drop paradigm for database objects since a role has no attributes that can be modified. Its actual effect is to alter an attribute of the database: Firebird uses it to enable and disable the capability for Windows Adminstrators to assume administrator privileges automatically when logging in.
This procedure can affect only one role: the system-generated role RDB$ADMIN
that exists in every database of ODS 11.2 or higher. Several factors are involved in enabling this feature.
For details, see AUTO ADMIN MAPPING in the Security chapter.
5.15.3. DROP ROLE
Used for
Deleting a role
Available in
DSQL, ESQL
Syntax
DROP ROLE rolename
The statement DROP ROLE
deletes an existing role. It takes just a single argument, the name of the role. Once the role is deleted, the entire set of privileges is revoked from all users and objects that were granted the role.
A role can be deleted by its owner or by an administrator.
Example
Deleting the role SELLERS:
DROP ROLE SELLERS;
See also