ranamahmud

const userId =  db.user.findOne(
       { "phoneNumber" : "phoneNumber" }
   );
   
const uid = userId._id;


const employee =  db.user.findOne(
       { "userId" : uid }

ranamahmud

try {
   db.studentCollection.updateMany(
      { status: "pending" },
      { $set: { "status" : "verified" } }
   );
} catch (e) {
   print(e);
}

ranamahmud

let num3 = 100;
function total(num1, num2) {
    let result = num1 + num2 + num3;
    console.log("Result inside: " + result);
    return result;
}

const output = total(13, 5);
// Result inside: 118
console.log(output);

ranamahmud

class Pet {
    constructor(name, age) {
        this.name = name;
        this.age = age;
    }
}

let pet1 = new Pet("Poltu", 2)
console.log(pet1);
// Pet { name: 'Poltu', age: 2 }

ranamahmud

// truthy values
// true, {}, [], any number, "0"
// "false" inside quote or any quoted string
// new Date()
// Infinity, -Infinity
// biginteger number
if (true) {
    console.log('condition is true');
} else {
    console.log('condition is false');

ranamahmud

const dog = {
    name: 'Dog',
    getName: function () {
        return this.name;
    },

    bark: function () {
        console.log(this.name + ". Bark bark ...")
    }
}

ranamahmud

const nums = [1, 2, 3, 4, 5, 6, 7, 8, 9];

function greater(num) {
    return num > 5;
}

const largeNumbers = nums.find(greater);
console.log(largeNumbers)
\\ 6
const largeNumbers2 = nums.find(number => number > 5);

ranamahmud

function popup() {
    console.log("Welcome to Bangladesh");
}
setTimeout(popup, 3000);

ranamahmud

const nums = [1, 2, 3, 4, 5, 6, 7, 8, 9];

function greater(num) {
    return num > 5;
}

const largeNumbers = nums.filter(greater);
console.log(largeNumbers)
\\  [ 6, 7, 8, 9 ]
const largeNumbers2 = nums.filter(number => number > 5);

ranamahmud

const nums = [1, 2, 3, 4, 5, 6, 7, 8, 9];

function double(num) {
    return num * 2;
}

const doubleNums = nums.map(double);
console.log(doubleNums)
\\ [2, 4, 6, 8, 10, 12, 14, 16, 18]
const doubleNums2 = nums.map(number => number * 2);