MongoDB架构设计，用于多项选择题和答案

Posted 2021-05-06

我不熟悉MongoDB的设计，我需要设计DB的帮助。存储问题的最佳结构是什么，具有答案选择和候选人的答案？

- 如果考生在第一次考试中失败，他们可以参加另外两门考试，每个考生将获得一组12个问题。因此，每个考试候选人每次都应该得到不同的问题。

- 每个考试的答案必须以12分中的分数记录，因为每个问题集为12。

答案

我为每个必需的细节创建了一个mongoose模式。你可以从中获得帮助。我已经分析了你的要求并为许多模式添加模型，第一个问题模式，导出为模型

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);

在QuestionSchema，我有一个AnswerOptionSchema嵌入

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
});

在这些模式的帮助下，我创建了一个QuestionSetSchema来添加一组问题模式

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);

现在准备了问题，答案选项和集合，现在需要设计候选模式，

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);

在这里，你会注意到，我也在计算候选人的总数和他在CandidateQuesAnswer模型中给出的每一组的答案。这个模型有类似的结构

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);

我在使用save提供的pre mongoose钩子之前，保存文档并计算值以声明候选通过或失败。

另一答案

以下是您可以使用的基本语法：

首先你需要像这样要求猫鼬：var mongoose = require（'mongoose'）;

然后你需要像这样创建Schema：

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

最后一步是创建一个这样的模型：var student = mongoose.model（'student'，studentSchema）;

这就是全部：这是基本结构。 :)