GRANT

The GRANT statement adds permissions for a role. It allows for setting permissions to databases, schemas, and tables.

It also allows adding a role as a memeber to another role.

When granting permissions to a role, the permission is added for existing objects only. To automatically add permissions to newly created objects, see ALTER DEFAULT PERMISSIONS.

Learn more about the permission system in the access control guide.

See also REVOKE, CREATE ROLE.

Syntax

The following is the syntax for the ``GRANT` statement:

grant_statement ::=
   {
   -- Grant permissions at the cluster level:
   GRANT
      { SUPERUSER
      | LOGIN
      | PASSWORD 'password'
      }
      TO role_name [, ...]

   -- Grant permissions at the database level:
   | GRANT
      {
         { CREATE
         | CONNECT
         | DDL
         | SUPERUSER
         | CREATE FUNCTION
         } [, ...]
      | ALL [PERMISSIONS]
      }
      ON DATABASE database_name [, ...]
      TO role_name [, ...]

   -- Grant permissions at the schema level:
   | GRANT
      {
         { CREATE
         | DDL
         | USAGE
         | SUPERUSER
         } [, ...]
      | ALL [PERMISSIONS ]
      }
      ON SCHEMA schema_name [, ...]
      TO role_name [, ...]

   -- Grant permissions at the object level:
   | GRANT
      {
         { SELECT
         | INSERT
         | DELETE
         | DDL
         } [, ...]
      | ALL [PERMISSIONS]
      }
      ON { TABLE table_name [, ...] | ALL TABLES IN SCHEMA schema_name [, ...]}
      TO role_name [, ...]


   -- Grant execute function permission:
   | GRANT
      { ALL
      | EXECUTE
      | DDL
      }
      ON FUNCTION function_name
      TO role_name [, ...]


   -- Pass permissions between roles by granting one role to another:
   | GRANT role_name [, ...]
      TO role_name_2
      [ WITH ADMIN OPTION ]

   ;

role_name ::= identifier

role_name2 ::= identifier

database_name ::= identifier

table_name ::= identifier

schema_name ::= identifier

Parameters

The following table describes the GRANT parameters:

Parameter	Description
role_name	The name of the role to grant permissions to
table_name, database_name, schema_name, function_name	Object to grant permissions on.
WITH ADMIN OPTION	If WITH ADMIN OPTION is specified, the role that has the admin option can in turn grant membership in the role to others, and revoke membership in the role as well. Without the admin option, ordinary roles cannot grant or revoke membership. Roles with SUPERUSER can grant or revoke membership in any role to anyone.

Supported Permissions

The following table describes the supported permissions:

Permission	Object	Description
LOGIN	Cluster	Login permissions (with a password) allows a role to be a user and login to a database
PASSWORD	Cluster	Sets the password for a user role
CREATE FUNCTION	Database	Allows a user to create a Python UDF
SUPERUSER	Cluster, Database, Schema	The most privileged role, with full control over a cluster, database, or schema
CONNECT	Database	Allows a user to connect and use a database
CREATE	Database, Schema, Table	For a role to create and manage objects, it needs the CREATE and USAGE permissions at the respective level
USAGE	Schema	For a role to see tables in a schema, it needs the USAGE permissions
SELECT	Table	Allows a user to run SELECT queries on table contents
INSERT	Table	Allows a user to run COPY FROM and INSERT statements to load data into a table
UPDATE	Table	Allows a user to modify the value of certain columns in existing rows without creating a table
DELETE	Table	Allows a user to run DELETE, TRUNCATE statements to delete data from a table
DDL	Database, Schema, Table, Function	Allows a user to alter tables, rename columns and tables, etc.
EXECUTE	Function	Allows a user to execute UDFs
ALL	Cluster, Database, Schema, Table, Function	All of the above permissions at the respective level

Examples

This section includes the following examples:

Creating a User Role with Log-in Permissions

The following example shows how to convert a role to a user by granting password and log-in permissions:

CREATE ROLE new_role;
GRANT LOGIN to new_role;
GRANT PASSWORD 'Tr0ub4dor&3' to new_role;
GRANT CONNECT ON DATABASE master to new_role; -- Repeat for other desired databases

Promoting a User to a Superuser

The following is the syntax for promoting a user to a superuser:

-- On the entire cluster
GRANT SUPERUSER TO new_role;

-- For a specific database
GRANT SUPERUSER ON DATABASE my_database TO new_role;

Creating a New Role for a Group of Users

The following example shows how to create a new role for a group of users:

-- Create new users (we will grant them passwords and logins later)
CREATE ROLE dba_user1;
CREATE ROLE dba_user2;
CREATE ROLE dba_user3;

-- Add new users to the existing r_database_architect role
GRANT r_database_architect TO dba_user1;
GRANT r_database_architect TO dba_user2;
GRANT r_database_architect TO dba_user3;

Granting with Admin Option

If WITH ADMIN OPTION is specified, the role with the admin option can grant membership in the role to others and revoke membership, as shown below:

-- dba_user1 is our team lead, so he should be able to grant
-- permissions to other users.

GRANT r_database_architect TO dba_user1 WITH ADMIN OPTION;

Changing Password for User Role

The following is an example of changing a password for a user role. This is done by granting the user a new password:

GRANT  PASSWORD  'new_password'  TO  rhendricks;

Note

Granting a new password overrides any previous password. Changing the password while the role has an active running statement does not affect that statement, but will affect subsequent statements.

Permissions

To grant permissions, the current role must have the SUPERUSER permission, or have the ADMIN OPTION.