ALTER TABLESPACE

Purpose

This statement is used to modify the encryption method of a tablespace.

Privilege requirements

To execute the ALTER TABLESPACE statement, the current user must have the CREATE TABLESPACE management privilege. For more information about OceanBase Database privileges, see Privilege classification in MySQL-compatible mode.

Syntax

• Modify the encryption method of an encrypted tablespace.

  ALTER TABLESPACE tablespace_name ENCRYPTION [=] 'tablespace_encryption_option';
  
  tablespace_encryption_option:
      N
      | Y
      | AES-256
      | AES-256-GCM
      | AES-128
      | AES-128-GCM
      | AES-192
      | AES-192-GCM
      | SM4-CBC
      | SM4-GCM
  

• Modify a tablespace.

  ALTER TABLESPACE tablespace_name
    {ADD | DROP} DATAFILE 'file_name'
    [INITIAL_SIZE [=] size]
    [WAIT]
    ENGINE [=] engine_name
  

  Notice

  Only the syntax with the keyword is supported, and the feature is not effective. The keyword cannot be used with ENCRYPTION. Otherwise, an error will be returned.

Parameters

tablespace_encryption_option

• N: No encryption.
• Y: If Y is specified, the default encryption algorithm is AES-256.
• AES-256: Uses a 256-bit key for encryption and decryption.
• AES-256-GCM: Uses a 256-bit key in GCM mode.
• AES-128: Uses a 128-bit key for encryption and decryption.
• AES-128-GCM: Uses a 128-bit key in GCM mode.
• AES-192: Uses a 192-bit key for encryption and decryption.
• AES-192-GCM: Uses a 192-bit key in GCM mode.
• SM4-CBC: SM4 algorithm in CBC mode, where each data block is XORed with the output of the previous block before encryption.
• SM4-GCM: SM4 algorithm in GCM mode, which provides both data encryption and authentication.

Examples

Change the encryption method of the unencrypted tablespace tablespace001 to use the SM4-GCM encryption algorithm.

ALTER TABLESPACE tablespace001 ENCRYPTION = 'SM4-GCM';