Grails GORM: How do I create a composite primary key and use it for a table relationship?

Question

I have two tables, one of which (legacy table: A) has two fields that should serve as a composite foreign key and the other one (new table: B) should use a composite primary key

Answer 1

Did you try to use attribute name instead of use attribute value ?

class B implements Serializable{
    String name;
    String className;
    String eventName;

    static mapping = {
        //supposed to make a composite PK
        id composite:['className', 'eventName'] 
    }
}

And mapping in A :

class A {
    static hasMany = [ b : B ]
}

No need to have className or eventName in A