我有一个像这样的家庭架构（其孩子在学校注册）…
var familySchema = new Schema({
parents: [{
firstName: String,
lastName: String,
email: String,
}],
students: [{
firstName: String,
lastName: String,
grade: Number,
}]
});
我想描述许多有教室的学校，教室里有学生，像这样…
var schoolSchema = new Schema({
name: String,
street: String,
classrooms: [{
classroomNumber: Number,
students: [ /* I am mixed up here */ ]
}]
});
我如何告诉猫鼬我想要一个在其他集合中找到的学生的对象ID数组？
我从这个答案中了解到，如果我想让教室参考家庭文件，我可以这样说：
families: { type : ObjectId, ref: 'Family' }
但是我如何对另一个集合的子文档做同样的事情呢？（如果不明显，我只是在学习mongo和猫鼬）。
如果要使用子文档引用，则需要更改对'学生'数组的引用。
var studentSchema = new Schema({
firstName: String,
lastName: String,
grade: Number,
});
var familySchema = new Schema({
parents: [{
firstName: String,
lastName: String,
email: String,
}],
students: [studentSchema]
});
var schoolSchema = new Schema({
name: String,
street: String,
classrooms: [{
classroomNumber: Number,
students: [ { type: ObjectId, ref: 'Family.students' }]
}]
});
var Student = mongoose.model('Student', studentSchema );
var Family = mongoose.model('Family ', familySchema );
var School = mongoose.model('School', schoolSchema );
