DCL Syntax Overview

Data control language (DCL) is used to create users and roles and set or modify database users or role rights.

Defining a Role

A role is used to manage permissions. For database security, management and operation permissions can be granted to different roles. For details about related SQL statements, see Table 1.

Table 1 SQL statements for defining a role

Description	SQL Statement
Creating a role	CREATE ROLE
Altering role attributes	ALTER ROLE
Dropping a role	DROP ROLE

Defining a User

A user is used to log in to a database. Different permissions can be granted to users for managing data accesses and operations of the users. For details about related SQL statements, see Table 2.

Table 2 SQL statements for defining a user

Description	SQL Statement
Creating a User	CREATE USER
Altering user attributes	ALTER USER
Dropping a user	DROP USER

Granting Rights

openGauss provides a statement for granting rights to data objects and roles. For details, see GRANT.

Revoking Rights

openGauss provides a statement for revoking rights. For details, see REVOKE.

Setting Default Rights

openGauss allows users to set rights for objects that will be created. For details, see .ALTER DEFAULT PRIVILEGES

Shutting Down The Current Node

openGauss allows users to run the shutdown command to shut down the current database node. For details, see SHUTDOWN.