Data Control Language (DCL) Command Reference
In order to assign privileges to users, administrators can use Data Control Language (DCL) statements. You can write and execute DCL statements like any other SQL statements against the system and databases. DCL statements allow you to quickly and easily grant or revoke privileges from users. DCL statements work off two main concepts: Grants and Revokes. Statements that begin with GRANT give the associated privileges to a user or group. Statements that begin with REVOKE remove those privileges from a user or group.
A full list of privileges can be found in the Ocient Privileges Reference.
Supported DCL Commands are:
- GRANT PRIVILEGE
- REVOKE PRIVILEGE
- GRANT ROLE
- REVOKE ROLE
The GRANT statement grants privileges to a user or group. The privileges that you can grant in the GRANT statement map to the tables and differ per object. The WITH GRANT OPTION keyword specifies that the grantee can also grant privileges on that object.
To grant privileges, you must have:
- VIEW privileges for the specified user or group being granted new privileges.
- SYSAUTH privileges over the system or database object that the specified user or group is being granted privileges on.
Syntax
When you grant any privilege to a user on a system or database object other than the VIEW privilege, the database implicitly grants the VIEW privilege on the specified object to the user as well.
Example
This example grants privileges for the SELECT SQL statement on a table to a trusted group.
For examples of granting privileges for individual users, see Grant Role Membership.
The REVOKE statement revokes privileges from a user or group.
To revoke privileges, you must have:
- VIEW privileges for the specified user or group having their privileges revoked.
- SYSAUTH privileges over the system or database object that the specified user or group is having their privileges revoked from.
Example
This example revokes the SELECT privilege on a table from an untrusted group.
For examples of revoking privileges for individual users, see Revoking Role Membership.
These tables describe the privilege options on each object in Ocient and the allowed privileges.
As of version 23.0, Ocient DCL has replaced the TRUNCATE privilege with the DELETE privilege.
Any TRUNCATE privileges, whether manually granted or assigned as part of a user role, should automatically convert to DELETE privileges following a system upgrade to version 23.0 or later.
Privilege | Description |
---|---|
CREATE [CONNECTION, DATABASE, USER] | The privilege to create the specified object type. On creation, the creating user inherits all privileges on the object. In the case of the DATABASE object, this is enforced by granting the creating user the newly created database administrator role as described in the Roles section. |
SYSAUTH | The privilege to grant and revoke all privileges on the system. |
USE | The ability to connect to the system. |
Privilege | Description |
---|---|
CREATE [ TABLE, VIEW, MLMODEL, USER, GROUP] | The privilege to create the specified object type. The user that creates the object inherits all privileges on the object. |
USE | Ability to connect to the database. Users created in this database are implicitly granted this privilege. |
ALTER | The ability to issue ALTER DATABASE commands on this database. |
DROP | The ability to drop this database. |
SYSAUTH | The ability to grant and revoke all privileges on the database. |
Privilege | Description |
---|---|
VIEW | Ability to see and read schema information about the view. |
SELECT | Ability to read data from the view. |
ALTER | Ability to modify the view. |
DROP | Ability to drop the view. |
SYSAUTH | Ability to grant privileges on the view. |
Privilege | Description |
---|---|
VIEW | Ability to see and read schema information about the table. |
SELECT | Ability to read data from the table. |
ALTER | Ability to modify the table. |
LOAD | Ability to load data into the table. |
DROP | Ability to drop the table. |
DELETE | Ability to delete and truncate the table. |
SYSAUTH | Ability to grant and revoke privileges on the table. |
INSERT | Ability to insert data into the table. |
Privilege | Description |
---|---|
ALTER | Ability to rename the model. |
SELECT | Ability to read data and descriptive data from the model. |
DROP | Ability to drop the model. |
SYSAUTH | Ability to grant and revoke privileges on the model. |
Privilege | Description |
---|---|
VIEW | Ability to read translation parameters. |
DROP | Ability to drop the translation. |
SYSAUTH | Ability to grant and revoke privileges on the translation. |
Privilege | Description |
---|---|
VIEW | Ability to read connection parameters. |
DROP | Ability to drop a connection. |
SYSAUTH | Ability to grant and revoke privileges on the model. |
Privilege | Description |
---|---|
VIEW | Ability to read information about the user. |
ALTER | Ability to modify the user. |
DROP | Ability to drop the user. |
SYSAUTH | Ability to grant rights and revoke privileges on the user. |
Privilege | Description |
---|---|
VIEW | Ability to read information about the group. |
ALTER | Ability to alter the group. |
DROP | Ability to drop the group. |
SYSAUTH | Ability to grant privileges on the group. |
The sys.privileges table in the system catalog exposes the privileges in the system. This table displays the following information:
- Timestamp of the grant
- Grantor
- Grantee
- Privilege granted
- Object type
- Object id
- Grantable
You can grant and revoke System Catalog VIEW and SELECT privileges just like ordinary tables. By default, everyone has VIEW and SELECT privileges on all system catalog tables.
You can see the objects within the system catalog tables only if you have sufficient privileges on those objects. These objects require a VIEW or SELECT privilege or membership in a group or role to provide visibility. When you execute queries against a system catalog table, you do not see nor know the existence of the objects where you do not have access.
Views offer a similar functionality because the database does not check privileges to the underlying tables and views after you create a view. You can create a table with sensitive information and restrict visibility by creating a view on top of the table with only certain rows or columns. Someone else with the SELECT privilege to the view can query the view, even without any privileges to the underlying table.
Similar to groups, users can inherit privileges by being granted one of the predefined roles in Ocient. The names of and privileges assigned to roles in Ocient are predefined by the system. Roles can be applicable to the Ocient system or one of the user-defined databases. The roles in Ocient are as follows:
System Roles
- Security Administrator: Can read, create, and modify all users and groups.
- System Administrator: Can read, create, and modify system objects such as tables, clusters, databases, etc. Can also kill running queries system-wide.
- System Analyst: Read-only access to the entire system.
Database Roles
- Administrator: Can read, create, and modify database objects such as tables, clusters, databases, etc. Can also create users for the database and kill running queries.
- Analyst: Read-only rights to database objects and data within the database.
For specifics on each Ocient role, see Default Role Privileges.
Grants a role to a user or group.
Syntax
Parameter | Data Type | Description |
---|---|---|
role_name | string | The name of a role to be granted to the specified user or group. Enclose this string in quotes. |
user_or_group_name | string | The name of a user or group to be granted the specified role. |
Example
This example grants user1 the system administrator role.
Revokes a role from a user or group.
Syntax
Parameter | Data Type | Description |
---|---|---|
role_name | string | The name of a role to be revoked for the specified user or group. Enclose this string in quotes. |
user_or_group_name | string | The name of a user or group to have the specified role revoked. |
Example
This example revokes the system administrator role from user1.
Target | Privileges |
---|---|
System | SYSAUTH, CREATE [ USER ] |
Database | SYSAUTH, CREATE [ USER, GROUP ] |
View | SYSAUTH |
Table | SYSAUTH |
Machine Learning Model | SYSAUTH |
Translation | VIEW, SYSAUTH |
Connection | SYSAUTH |
User | VIEW, ALTER, DROP, SYSAUTH |
Group | VIEW, ALTER, DROP, SYSAUTH |
Target | Privileges |
---|---|
System | USE, CREATE [ DATABASE, CONNECTION, USER ] |
Database |
|
View | VIEW, SELECT, ALTER, DROP |
Table | VIEW, SELECT, ALTER, LOAD, DROP, DELETE, INSERT |
Machine Learning Model | SELECT, DROP |
Translation | VIEW, DROP |
Connection | VIEW, DROP |
User | VIEW, ALTER, DROP |
Group | VIEW, ALTER, DROP |
Target | Privileges |
---|---|
System | USE |
Database | USE |
View | VIEW, SELECT |
Table | VIEW, SELECT |
Machine Learning Model | SELECT |
Translation | VIEW |
Connection | VIEW |
User | VIEW |
Group | VIEW |
Target | Privileges |
---|---|
Database |
|
View | VIEW, SELECT, ALTER, DROP |
Table | VIEW, SELECT, ALTER, LOAD, DROP, DELETE, INSERT, SYSAUTH |
Machine Learning Model | SELECT, DROP, SYSAUTH |
Translation | VIEW, DROP, SYSAUTH |
User | VIEW, ALTER, DROP, SYSAUTH |
Group | VIEW, ALTER, DROP, SYSAUTH |
Target | Privileges |
---|---|
Database | USE |
View | VIEW, SELECT |
Table | VIEW, SELECT, LOAD, DELETE, INSERT |
Machine Learning Model | SELECT |
Translation | VIEW |
User | VIEW |
Group | VIEW |