Function

ALTER REDACTION POLICY modifies a data redaction policy applied to a specified table.

Precautions

Only the table object owner and users with the gs_redaction_policy preset role can modify the masking policy.

Syntax

Modify the expression used for a redaction policy to take effect.

ALTER REDACTION POLICY policy_name ON table_name [INHERIT] WHEN (new_when_expression);

Enable or disable a redaction policy.

ALTER REDACTION POLICY policy_name ON table_name ENABLE | DISABLE;

Rename a redaction policy.

ALTER REDACTION POLICY policy_name ON table_name RENAME TO new_policy_name;

Add, modify, or delete a column on which the redaction policy is used.

ALTER REDACTION POLICY policy_name ON table_name 
    action;

There are several clauses of action:

[INHERIT] ADD COLUMN column_name WITH function_name ( arguments )
  | [INHERIT] MODIFY COLUMN column_name WITH function_name ( arguments )
  | DROP COLUMN column_name

Parameter Description

policy_name
Specifies the name of the redaction policy to be modified.
table_name
Specifies the name of the table to which the redaction policy is applied.
INHERIT
Specifies whether the masking policy or operation is inherited from other masking policies or operations. This parameter is not recommended.
new_when_expression
Specifies the new expression used for the redaction policy to take effect.
ENABLE | DISABLE
Specifies whether to enable or disable the current redaction policy.
- ENABLE
  Enables the redaction policy that was previously disabled for the table.
- DISABLE
  Disables the redaction policy currently applied to the table.
new_policy_name
Specifies the new name of the redaction policy.
column_name
Specifies the name of the table column to which the redaction policy is applied.

To add a column, use a column name that has not been bound to any redaction functions.

To modify a column, use the name of an existing column.

To delete a column, use the name of an existing column.
function_name
Specifies the name of a redaction function.
arguments
Specifies the list of arguments of the redaction function.
- MASK_NONE: indicates that no masking is performed.
- MASK_FULL: indicates that all data is masked to a fixed value.
- MASK_PARTIAL: indicates that partial masking is performed based on the specified character type, numeric type, or time type.

Examples

Modify the expression for a redaction policy to make it take effect for the specified role (If no user is specified, the redaction policy takes effect for the current user by default.):

ALTER REDACTION POLICY mask_emp ON emp WHEN (pg_has_role(current_user, 'redact_role', 'member'));
ALTER REDACTION POLICY mask_emp ON emp WHEN (pg_has_role('redact_role', 'member'));

Modify the expression for the data redaction policy to make it take effect for all users.

ALTER REDACTION POLICY mask_emp ON emp WHEN (1=1);

Disable the redaction policy.

ALTER REDACTION POLICY mask_emp ON emp DISABLE;

Enable the redaction policy again.

ALTER REDACTION POLICY mask_emp ON emp ENABLE;

Change the redaction policy name to mask_emp_new.

ALTER REDACTION POLICY mask_emp ON emp RENAME TO mask_emp_new;

Add a column with the redaction policy used.

ALTER REDACTION POLICY mask_emp_new ON emp ADD COLUMN name WITH mask_partial(name, '*', 1, length(name));

Modify the redaction policy for the name column. Use the MASK_FULL function to redact all data in the name column.

ALTER REDACTION POLICY mask_emp_new ON emp MODIFY COLUMN name WITH mask_full(name);

Delete an existing column where the redaction policy is used.

ALTER REDACTION POLICY mask_emp_new ON emp DROP COLUMN name;

Helpful Links

CREATE REDACTION POLICY, DROP REDACTION POLICY