grails - GORM不处理在其组合主键中具有进一步关联的关联的映射

Question

我正在尝试在GORM / Grails应用程序中映射现有表。大多数表具有复合主键(不是我的选择)。

我发现当我将一个关联映射到一个类( child 的 parent )时，父类的复合键也包含一个带有复合键的类(祖 parent )的关联，GORM不会费心检查非复合键中祖 parent 类和子对象的映射。

child

class Child implements Serializable {
    Parent parent
    String name

    belongsTo= [parent: Parent]

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

父

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'])
    }
}

尝试收集外键时，DDL生成失败。

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])

它创建的外键与父类的主键不匹配(它可以正确解密)。

Answer 1

尝试:

child

class Child implements Serializable {

    String name

    static belongsTo= [parent: Parent]

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

父

class Parent implements Serializable {
    String name

    //static belongsTo= [parent: Parent]  //why do you need this
    static belongsTo= [GrandParent  ]  //did you mean this
    static hasMany= [children: Child,grandParent: GrandParent  ]

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

GrandParent

class GrandParent implements Serializable {
    String name
    Integer luckyNumber

    static hasMany= [parents: Parent]

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