> For the complete documentation index, see [llms.txt](https://docs.postgresql.tw/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.postgresql.tw/reference/sql-commands/sql-alterpolicy.md).

# ALTER POLICY

### ALTER POLICY

ALTER POLICY — change the definition of a row-level security policy

### Synopsis

```

ALTER POLICY name ON table_name RENAME TO new_name

ALTER POLICY name ON table_name
    [ TO { role_name | PUBLIC | CURRENT_ROLE | CURRENT_USER | SESSION_USER } [, ...] ]
    [ USING ( using_expression ) ]
    [ WITH CHECK ( check_expression ) ]
```

### Description

`ALTER POLICY` changes the definition of an existing row-level security policy. Note that `ALTER POLICY` only allows the set of roles to which the policy applies and the `USING` and `WITH CHECK` expressions to be modified. To change other properties of a policy, such as the command to which it applies or whether it is permissive or restrictive, the policy must be dropped and recreated.

To use `ALTER POLICY`, you must own the table that the policy applies to.

In the second form of `ALTER POLICY`, the role list, *`using_expression`*, and *`check_expression`* are replaced independently if specified. When one of those clauses is omitted, the corresponding part of the policy is unchanged.

### Parameters

*`name`* : The name of an existing policy to alter.

*`table_name`* : The name (optionally schema-qualified) of the table that the policy is on.

*`new_name`* : The new name for the policy.

*`role_name`* : The role(s) to which the policy applies. Multiple roles can be specified at one time. To apply the policy to all roles, use `PUBLIC`.

*`using_expression`* : The `USING` expression for the policy. See [CREATE POLICY](/reference/sql-commands/sql-createpolicy.md) for details.

*`check_expression`* : The `WITH CHECK` expression for the policy. See [CREATE POLICY](/reference/sql-commands/sql-createpolicy.md) for details.

### Compatibility

`ALTER POLICY` is a PostgreSQL extension.

### See Also

[CREATE POLICY](/reference/sql-commands/sql-createpolicy.md), [DROP POLICY](/reference/sql-commands/sql-droppolicy.md)

***

原文：[PostgreSQL 18.6 Documentation](https://www.postgresql.org/docs/18/sql-alterpolicy.html)（英文原文，待翻譯）


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