級聯刪除不起作用（NHibernate）

Question

我有主從表，我想要級聯刪除更新，這意味着當我從客戶刪除記錄時，它應該自動刪除與該客戶相關的訂單。

這是表的定義：

客戶表：

  <class name = "Customer">

    <id name="ID" column="ID" type="string">
      <generator class="assigned" />
    </id>

    <property name = "FirstName"/>
    <property name = "LastName"/>
    <property name = "AverageRating"/>
    <property name = "Points"/>
    <property name = "HasGoldStatus"/>
    <property name = "MemberSince" type = "DateTime"/>

    <bag name="Orders" inverse="true" cascade="all-delete-orphan" >
      <key column="CustomerId"/>
      <one-to-many class="Orders"/>
    </bag>   
    
  </class>
</hibernate-mapping>

訂單表：

<?xml version = "1.0" encoding = "utf-8" ?>

<hibernate-mapping xmlns = "urn:nhibernate-mapping-2.2"
   assembly = "NHibernate_example_1" namespace = "NHibernate_example_1.Models">

  <class name = "Orders">        
    <id name = "ID">
      <generator class = "native"/>
    </id>

    <property name = "Ordered"/>
    <property name = "Shipped"/>

    <many-to-one name="Customer" column="CustomerId" class="Customer" />
  </class>

</hibernate-mapping>

但是在創建表后 FK 有這個屬性：

CONSTRAINT FK_E4664020 FOREIGN KEY ( CustomerId ) REFERENCES customer ( ID ) ON UPDATE RESTRICT ON DELETE RESTRICT

如何設置ON UPDATE CASADE ON DELETE CASCADE ？

我正在使用 MySQL 和 nHibernate 5.3.0