Assignment Model

Overview

This document describes the data model used for managing assignments and their submissions in the academic system. The Assignment model includes both assignment metadata and embedded student submissions.

Model

Assignment Model

The Assignment model represents course assignments and the submissions made by students.

Schema Definition

// Embedded Submission Schema
const submissionSchema = new mongoose.Schema({
  studentRollNo: {
    type: String,
    required: true,
    ref: 'Student' // reference by rollNo
  },
  studentName: {
    type: String,
    required: true
  },
  content: {
    type: String,
    required: true
  },
  submittedAt: {
    type: Date,
    default: Date.now
  }
}, { _id: false });

// Main Assignment Schema
const assignmentSchema = new mongoose.Schema({
  assignmentNumber: {
    type: Number,
    required: true,
  },
  courseCode: {
    type: String,
    required: true,
    ref: 'Course'
  },
  title: {
    type: String,
    required: true
  },
  description: {
    type: String
  },
  dueDate: {
    type: Date,
    required: true
  },
  submissions: [submissionSchema],
  createdAt: {
    type: Date,
    default: Date.now
  },
  updatedAt: {
    type: Date,
    default: Date.now
  }
});

Fields (Assignment Schema)

Field	Type	Required	Default	Description
assignmentNumber	Number	Yes	-	Identifier for the assignment
courseCode	String	Yes	-	Code of the course the assignment belongs to, references the Course model
title	String	Yes	-	Title of the assignment
description	String	No	-	Detailed description of the assignment
dueDate	Date	Yes	-	Deadline for submitting the assignment
submissions	[submissionSchema]	No	[]	List of student submissions embedded in the assignment document
createdAt	Date	No	Date.now	Timestamp when the assignment was created
updatedAt	Date	No	Date.now	Timestamp when the assignment was last updated

Fields (Submission Schema)

Field	Type	Required	Default	Description
studentRollNo	String	Yes	-	Roll number of the student submitting the assignment
studentName	String	Yes	-	Full name of the student
content	String	Yes	-	Content or answer submitted by the student
submittedAt	Date	No	Date.now	Timestamp when the student submitted the assignment

Relationships

• Course (Many-to-One): Each assignment belongs to one course.
• Student (Embedded, One-to-Many): Each assignment may contain multiple student submissions.

Usage

The Assignment model is used to: - Store assignment details for different courses - Track and manage student submissions for each assignment - Enforce submission deadlines and store submission timestamps

Model Registration

export const Assignment = mongoose.model('Assignment', assignmentSchema);

The Assignment model is registered with Mongoose and exported for use throughout the application.

Database Considerations

Indexing

Indexing may be beneficial on the following fields: - assignmentNumber and courseCode for querying assignments by course and number - submissions.studentRollNo for efficient lookups of specific student submissions

Data Validation

The schema includes validation mechanisms: - Required fields for both assignment and submission schemas - Embedded submission schema for encapsulated submission data - Default values for timestamps

Performance Considerations

• Embedded submissions reduce the need for joins but could grow large for popular courses
• Updates to submission content require writing to the entire assignment document
• Embedded documents allow atomic updates to a student's submission for a given assignment