Hologres:User management

Limits

By default, custom accounts cannot query MaxCompute foreign tables. To enable this capability, you must configure USER MAPPING. For more information, see FAQ.

Add a user

Delete a user

On the Users page, select the target instance name. In the user list, find the user that you want to delete and click Delete in the Actions column. This action removes the user from the instance and revokes all access permissions.

Create a custom user

Console operations

You can create custom users for an instance on the user management page.

1. On the Users page, select the target instance name and click Create Custom User in the upper-right corner.

2. In the Create Custom User dialog box, configure the following parameters.

   Parameter	Description
   Custom account	Enter a custom account name. The name can be up to 57 characters long and can contain only lowercase letters, digits, and underscores (_).
   Select member role	Select a user type. Superuser: Has all permissions for the instance. If a RAM user is granted Superuser permissions, no other authorization is needed. Normal User: Is only created in the instance and has no permissions to view or operate on any objects, such as databases, schemas, and tables. You must grant permissions to a normal user before they can view or operate on the instance.
   Password	Set a password that meets the following requirements. Must contain at least three of the following character types: uppercase letters, lowercase letters, digits, and special characters. Must be 8 to 32 characters in length. Supported special characters include !@#$%^&*()_+-=.
   Confirm password	Enter the password again.

3. Click OK to create the custom user.

SQL operations

create user "BASIC$<user_name>" with password '<password>';

user_name specifies the custom username. password specifies the password for the custom user.

Other related operations

• Modify the password for a custom user.

  Note

  You can modify the passwords of only custom users. Alibaba Cloud accounts and RAM users use automatically generated AccessKey pairs for authentication instead of passwords.

  You can use one of the following methods to modify the password of a custom user:

  • Console operations.

    1. On the Users page, find the target custom user in the User Account Authorization list and click Reset Password in the Actions column.

    2. In the Reset Password dialog box, enter and confirm the new password, and then click OK.

  • SQL operations.

    alter user "BASIC$<user_name>" with password '<password>';

    user_name specifies the custom username. password specifies the new password for the custom user.

• Delete a custom user.

  You can use one of the following methods to delete a custom user:

  • Console operations.

    1. On the Users page, find the target custom user in the User Account Authorization list and click Delete in the Actions column.

    2. In the Remove User dialog box, click OK.

  • SQL operations.

    drop user "BASIC$<user_name>";

    user_name specifies the custom username.

FAQ

• Symptom: The following error occurs when a custom account tries to access a MaxCompute foreign table.

  ERROR:  Query:[xxxxxx] Build desc failed: failed to check permission: Authorization Failed [4002], You don't exist in project hologres_test. Context ID:xxxxxx-xxxx-xxxx-xxxx-xxxxxxx.    --->Tips: Pricipal:INVALID$BASIC$xxx; You don't exist in project xxx

• Cause: Custom accounts exist only within Hologres and cannot access MaxCompute foreign tables by default.

• Solution: You can create a User Mapping in Hologres. This action attaches a custom account to an Alibaba Cloud RAM user who has the required database permissions for the corresponding MaxCompute project and Hologres internal tables.

  • Syntax example

    CREATE USER MAPPING
    FOR "<user_name>"
    SERVER odps_server
    OPTIONS
    (
        access_id '<Access_id>',
        access_key '<Access_key>'
    );

  • Parameter description

    Parameter	Description
    user_name	The username of the custom account.
    Access_id	The AccessKey ID of an account that has logon permissions for the current database. Click AccessKey Management to obtain the AccessKey ID.
    Access_key	The AccessKey secret of an account that has logon permissions for the current database. Click AccessKey Management to obtain the AccessKey secret.

  • Usage example

    -- Create a USER MAPPING for the user BASIC$test
    CREATE USER MAPPING
    FOR "BASIC$test"
    SERVER odps_server
    OPTIONS (
      access_id 'LTxxxxxxxxxx',
      access_key 'y8xxxxxxxxxxxxx');
    
    -- Create a USER MAPPING for the current user
    CREATE USER MAPPING
    FOR CURRENT_USER
    SERVER odps_server
    OPTIONS (
      access_id 'LTxxxxxxxxxx',
      access_key 'y8xxxxxxxxxxxxx');

References

For more information about how to delete an account (DROP USER) in Hologres and troubleshoot related errors, see Delete an account.