GORM不处理在复合主键中具有进一步关联的关联的映射 [英] GORM doesn't handle mapping of associations which have a further association in their composite primary key

问题描述

我试图在GORM / Grails应用程序中映射现有表。大多数表都有复合主键（不是我的选择）。

我发现当我将一个关联映射到一个类父类）在父类的组合键包含一个具有组合键的类的关联（祖父母）的情况下，GORM不会检查祖父母类和子类在非组合键中的映射。

Child

 可序列化{
父母
字符串名称
 
 belongsTo = [父：父] 
 
静态映射= {
 id（合成：[ 'parent'，'name']）
} 
} 
  

Parent

 类父类实现Serializable {
 GrandParent grandParent 
字符串名称
收集< Child> children 
 
 belongsTo = [grandParent：GrandParent] 
 hasMany = [children：Child] 
 
 static mapping = {
 id（composite：['grandParent '，'name']）
} 
} 
  

GrandParent

  class GrandParent实现Serializable {
字符串名称
整数luckyNumber 
 Collection<亲本GT​​;父母
 
 hasMany = [父母：父母] 
 
静态映射= {
 id（合成：['name'，'luckyNumber']）
 } 
} 
  

尝试收集外键时，DDL生成失败。

  org.hibernate.MappingException：
外键（FK_1：CHILD [parent_grandparent_id，parent_name]））
必须有与引用的主键
（PARENT [parent_grandparent_name，parent_grandparent_lucky_number，parent_name]）
  

创建的外键与父类的主键（它可以正确解译）不匹配。 解决方案

我已经问过关于Grails Slack #gorm的问题，这似乎在Gorm映射中出现了一个空白。

我已经在Grails数据映射程序中引发了一个问题等。我们会看看这是怎么回事。

I'm trying to map existing tables in a GORM/Grails app. Most of the tables have composite primary keys (not my choice).

I'm finding that when I map an association to a class (parent of a child) where the composite key of the parent class contains an association to a class with a composite key also (grandparent), GORM doesn't bother to check the mapping of the grandparent class and subs in a non-composite key.

Child

class Child implements Serializable {
    Parent parent
    String name

    belongsTo= [parent: Parent]

    static mapping= {
        id(composite: ['parent', 'name'])
    }
}

Parent

class Parent implements Serializable {
    GrandParent grandParent
    String name
    Collection<Child> children

    belongsTo= [grandParent: GrandParent]
    hasMany= [children: Child]

    static mapping= {
        id(composite: ['grandParent', 'name'])
    }
}

GrandParent

class GrandParent implements Serializable {
    String name
    Integer luckyNumber
    Collection<Parent> parents

    hasMany= [parents: Parent]

    static mapping= {
        id(composite: ['name', 'luckyNumber'])
    }
}

The DDL generation fails when trying to glean the foreign keys.

org.hibernate.MappingException:
Foreign key (FK_1:CHILD [parent_grandparent_id,parent_name]))
    must have same number of columns as the referenced primary key
(PARENT [parent_grandparent_name,parent_grandparent_lucky_number,parent_name])

The foreign key it's created does not match the primary key of the parent class (which it was able to decipher correctly).

解决方案

I've asked around on Grails Slack #gorm, and this appears to hit a gap in Gorm mapping.

I've raised an issue in the Grails data mapping project. We'll see where this goes.

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