MongoDB schema design for multpile choice questions and answers

I have created a mongoose schema for each required details. You can take help from it. I have analyzed a bit your requirements and adding models for many schemas, first question schema, exported as a model

import { Schema } from 'mongoose';import { AnswerOptionSchema } from './answer-option-schema';const mongoose = require('mongoose');export const QuestionSchema: Schema = new Schema({  question: {    type: String,    minlength: 10,    maxlength: 1000,  },  answerOptions: {    type: [AnswerOptionSchema],    default: undefined,    validate: {      validator: function(value: any) {        return value && value.length === 4;      },      message: 'Answer options should be 4.'    }  }}, {  timestamps: true});export const Question = mongoose.model('Question', QuestionSchema);

and here in the QuestionSchema, I have embedded an AnswerOptionSchema as

import { Schema } from 'mongoose';export const AnswerOptionSchema: Schema = new Schema({  optionNumber: {    type: Number  },  answerBody: {    type: String,    minlength: 1,    maxlength: 200,  },  isCorrectAnswer: { // you can store the correct answer with question id in another model.    type: Boolean,    default: false  }}, {  _id: false});

With the help of these schemas, I have created a QuestionSetSchema to add a set of question schema as

import { Schema } from "mongoose";import { QuestionSchema } from "./question-schema";const mongoose = require('mongoose');export const QuestionSetSchema: Schema = new Schema({  questionSet: {    type: [QuestionSchema],    validate: {      validator: function(value: any) {        return value.length === 12;      },      message: 'Question set must be 12.'    }  },}, {  timestamps: true});export const QuestionSet = mongoose.model('QuestionSet', QuestionSetSchema);

Now prepared with the question, answer options and the set, now need to design the candidate schema,

import { Schema } from "mongoose";const mongoose = require('mongoose');export const CandidateSchema: Schema = new Schema({  name: String,  email: String, // you can store other candidate related information here.  totalAttempt: {    type: Number,    default: 0,    validate: {      validator: function(value: number) {        return value === 3;      },      message: 'You have already done three attempts.'    }  },  candidateQuestionAnswers: {    type: [Schema.Types.ObjectId],    ref: 'CandidateQuesAnswer'  }}, {  timestamps: true});export const Candidate = mongoose.model('Candidate', CandidateSchema);

Here, you will notice, I am also calculating the totalAttempt of the candidate and the answers for each set given by him in the CandidateQuesAnswer model. This model has the structure like

import { Schema } from "mongoose";export const CandidateQuesAnswerSchema = new Schema({  candidate: {    type: Schema.Types.ObjectId,    ref: 'Candidate'  },  questionSet: {    type: Schema.Types.ObjectId,    ref: 'QuestionSet'  },  questionAnswers: {    type: [Number] // You can add answer schema  },  totalScore: {    type: Number  },  isPassed: {    type: Boolean,    default: false  }}, {  timestamps: true});CandidateQuesAnswerSchema.pre('save', function updateTotalScore(next) {  // update total score of the candidate here based on the correct questionAnswers and  // questionSet.  next();});CandidateQuesAnswerSchema.pre('save', function updateIsPassed(next) {  // update the isPassed based on the totalScore obtained by the candidate.  next();});export const CandidateQuesAnswer = mongoose.model('CandidateAnswer', CandidateQuesAnswerSchema);

Where I have used pre save hooks provided by mongoose, before saving the document and calculating the values to declare the candidate pass or fail.

Here is basic syntax you can use:

First You need To require the mongoose like this:var mongoose = require('mongoose');

Then You need To create Schema like this:

var studentSchema = mongoose.Schema({ name: String, email: String,});

And Final Step is to create a model like this:var student = mongoose.model('student', studentSchema);

That's all:This is the basic structure.:)