为什么 Mongo 给我 E11000 错误,即使我没有将任何字段设置为唯一?

Why is Mongo giving me the E11000 error even though I don't have any field set to unique?

将第二个文档保存到 MongoDB atlas 时出现此错误:

error:MongoError: E11000 duplicate key error collection: test.orders index: orderId_1 dup key: { orderId: null }

但是,在文档架构中,我没有将任何字段设置为唯一:

const orderSchema = new Schema({
    paymentId: {
        type: Number
    },
    paymentStatus: {
        type: String
    },
    paymentToken: {
        type: String
    },
    orderDetails: {
        type: Object
    },
}, {
    timestamps: true
});

错误是什么意思? 我是这样保存的:

const newOrder = new Order({
        paymentId, 
        paymentStatus, 
        orderDetails,
        paymentToken
    });
    
    newOrder.save()
        .then(() => console.log("order saved!"))
        .catch(err => console.log("error:" + err));

错误消息引用了我在您的模型中没有看到的 OrderId_1。我会检查指南针或地图集以确保您没有设置“唯一”索引。