ALTER SERVER

Function

ALTER SERVER adds, modifies, or deletes the parameters of an existing server. You can query existing servers from the pg_foreign_server system catalog. The current feature is a lab feature. Contact Huawei technical support before using it.

Precautions

Only the server owner or a user granted with the ALTER permission can run the ALTER SERVER command. The system administrator has this permission by default. To change the owner of a server, the current user must be the owner of the server or the system administrator, and the user must be a member of the new owner role.

When multi-layer quotation marks are used for sensitive columns (such as password and secret_access_key) in OPTIONS, the semantics is different from that in the scenario where quotation marks are not used. Therefore, sensitive columns are not identified for anonymization.

Syntax

• Change the parameters for a foreign server.

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ALTER SERVER server_name [ VERSION 'new_version' ]
    [ OPTIONS ( {[ ADD | SET | DROP ] option ['value']} [, ... ] ) ];

In OPTIONS, ADD, SET, and DROP are operations to be performed. If these operations are not specified, ADD operations will be performed by default. option and value are the parameters of the corresponding operation.

• Change the owner of a foreign server.

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ALTER SERVER server_name 
    OWNER TO new_owner;

• Change the name of a foreign server.

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ALTER SERVER server_name 
    RENAME TO new_name;

Parameter Description

The parameters for modifying the server are as follows:

• server_name

  Specifies the name of the server to be modified.

• new_version

  Specifies the new version of the server.

• The server parameters in OPTIONS are as follows:
  • encrypt

    Specifies whether to encrypt data. This parameter can be set only when type is set to OBS. The default value is off.

    Value range:

    • on indicates that data is encrypted.
    • off indicates that data is not encrypted.
  • access_key

    Specifies the access key (AK) (obtained by users from the OBS console) used for the OBS access protocol. When you create a foreign table, the AK value is encrypted and saved to the metadata table of the database. This parameter is available only when type is set to OBS.

  • secret_access_key

    Specifies the SK value (obtained by users from the OBS console) used for the OBS access protocol. When you create a foreign table, the SK value is encrypted and saved to the metadata table of the database. This parameter is available only when type is set to OBS.

• new_owner

  Specifies the new owner of the server. To change the owner, you must be the owner of the foreign server and a direct or indirect member of the new owner role, and must have the USAGE permission on the encapsulator of the foreign server.

• new_name

  Specifies the new name of the server.

Helpful Links

CREATE SERVER, CREATE SERVER