js 增删改查

let fruits = ['apple', 'banana'];
fruits.push('orange'); // 增加元素
console.log(fruits); // 输出: ['apple', 'banana', 'orange']

let fruits = ['apple', 'banana', 'orange'];
fruits.splice(1, 1); // 从索引1开始删除1个元素
console.log(fruits); // 输出: ['apple', 'orange']

let users = [
    { id: 1, name: 'Alice' },
    { id: 2, name: 'Bob' }
];
users[1].name = 'Bobby'; // 修改第二个用户的名字
console.log(users); // 输出: [{ id: 1, name: 'Alice' }, { id: 2, name: 'Bobby' }]

let fruits = ['apple', 'banana', 'orange'];
let fruitToFind = 'banana';
let index = fruits.indexOf(fruitToFind); // 查询元素索引
console.log(index); // 输出: 1

db.collection('users').insertOne({ name: 'Charlie', age: 25 });

db.collection('users').deleteOne({ name: 'Bob' });

db.collection('users').updateOne(
    { name: 'Alice' },
    { $set: { age: 26 } }
);

db.collection('users').find({}).toArray((err, results) => {
    console.log(results);
});