当我尝试以这种方式连接数据库时，它会给出此错误，而我之前已经成功地连接了数据库。

const mongoose = require('mongoose');
require('dotenv').config();

exports.dbConnect = () => {
    mongoose.connect("mongodb://localhost:27017/cloudinaryEntry", {
        useNewUrlParser : true,
        useUnifiedTopology : true,
    })
    .then( () => console.log("Database connected successfully"))
    .catch( (error) => console.log("Error in connected database", error));
}

Here is the code and error
但当我添加另一个属性“家庭：4“，然后成功连接。”有人能告诉我为什么会这样吗？***

const mongoose = require('mongoose');
require('dotenv').config();
exports.dbConnect = () => {
    mongoose.connect("mongodb://localhost:27017/cloudinaryEntry", {
        useNewUrlParser : true,
        useUnifiedTopology : true,
        family : 4
    })
    .then( () => console.log("Database connected successfully"))
    .catch( (error) => console.log("Error in connected database", error));
}

**Here is the Code