How to create a composite primary Key in django

 To create a composite primary key based on the first three columns (classdate, course_code, and batch_number), you need to define a unique_together constraint in the model's Meta class. Here's how you can do it:

from django.db import models

class DailyWork(models.Model):
    classdate = models.DateField()
    course_code = models.ForeignKey(Course, on_delete=models.DO_NOTHING)
    batch_number = models.ForeignKey(Batch, on_delete=models.DO_NOTHING)
    s1st = models.CharField(max_length=7)
    s1endt = models.CharField(max_length=7)

    
    class Meta:
        ordering = ['id']
        unique_together = (('classdate', 'course_code', 'batch_number'),)

In this code, unique_together is a tuple of tuples where 
each inner tuple represents the fields that should be unique together. 
In this case, it ensures that the combination of classdate, course_code, and batch_number is unique,

effectively creating a composite primary key.

Make sure to replace Course and Batch with the actual models you are referencing.