Now there are two schemas, one is students and the other is students’ employment information

var Student = new mongoose.Schema({
    jobs:[{
        type:ObjectId,
        ref: 'job'
    }]
});

var job = new mongoose.Schema({
    student:{
        type: ObjectId,
        ref: 'student'
    }
})

删除一条job文档的时候如何把学生文档的jobs数组中该job的ObjectId也删了，
我用了如下的写法：
Job.remove({_id:_id}, function(err,job){
    var jobId = job._id;
    Student.update({_id：StudentId},{
    $pull:{jobs:{ObjectId: jobId}}
    }, function(){})
})

This will report an error, what is the correct way to write it