当belongsTo指定多个类时，Grails属于级联删除吗？ [英] Grails belongsTo cascade on delete when belongsTo specifies multiple classes?

问题描述

  class所有者{
 static hasMany = Dog 
} 
 class Sitter {
 static hasMany = Dog 
} 
 class Dog {
 static belongsTo = [Owner，Sitter] 
} 
  

我的问题是：如果我创建一个Dog实例D，一个所有者实例O，一个Sitter实例S并将D与O和S关联，当S被删除时O会发生什么？ O还会有D吗？既然是级联删除，S和D都会被删除，对吧？当O发生什么事情？它还会有D吗？我已经测试过了，它遵循级联规则：如果你删除了所有者，那么Dog将会是删除级联，但Sitter将保持。

这是合理的：Sitter与所有者无关。 Sitter应该与所有者一起被删除是不合逻辑的，只是因为他与Owner有共同的属性。

class Owner {
    static hasMany = Dog
}
class Sitter {
    static hasMany = Dog
}
class Dog {
    static belongsTo = [Owner, Sitter]
}

My question is: If I create a Dog instance D, a Owner instance O, a Sitter instance S and associate D with both O and S, what happens to O when S gets deleted? Would O still have D? Since it's a cascade-delete, both S and D would get deleted, right? When what happens to O? Would it still have D?

解决方案

I have tested it, it follows the cascade rule: if you delete Owner, Dog will be deleted by cascade, but Sitter will remain.

And it's reasonable: Sitter is independent with Owner. It's illogical that Sitter should be deleted along with Owner, just because he has some common properties with Owner.

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