# DROP RULE

DROP RULE — 移除覆寫規則

### 語法

```
DROP RULE [ IF EXISTS ] name ON table_name [ CASCADE | RESTRICT ]
```

### 說明

DROP RULE 用於移除覆寫規則。

### 參數

`IF EXISTS`

如果規則不存在，請不要拋出錯誤。在這種情況下發出 NOTICE。

*`name`*

要移除的規則名稱。

*`table_name`*

規則適用的資料表或檢視表名稱（可加入綱要限定）。

`CASCADE`

自動移除相依於規則的物件，以及相依於這些物件的所有物件（請參閱[第 5.13 節](/15/the-sql-language/ddl/dependency-tracking.md)）。

`RESTRICT`

如果任何物件相依於它，則拒絕移除規則。這是預設行為。

### 範例

要移除覆寫規則 newrule：

```
DROP RULE newrule ON mytable;
```

### 相容性

DROP RULE 是 PostgreSQL 語法的延伸功能，整個查詢覆寫系統也是。

### 參閱

[CREATE RULE](/15/reference/sql-commands/create-rule.md), [ALTER RULE](/15/reference/sql-commands/alter-rule.md)


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