So the title states my objective. Here's the code I wrote to achieve it:
#for each cycle in instructional cycles:
for cycle in Instructional_Cycle.objects.all():
#for each standard in the currently selected cycle:
for standard in cycle.standards.all():
#generate random percentage of correct grade-level students to pass that standard, say between 20 and 90%
percent_pass = randint(20,90)
#calculate number of total students for that grade-level that percentage represents (percentage times total number of students in that grade)
total_students_passing = (percent_pass/100) * Student.objects.filter(grade_level = standard.grade_level).count()
already_selected = []
#while length of list of already selected students < total needed
while len(already_selected) < total_students_passing:
#select a random student out of that grade
count = Student.objects.filter(grade_level=standard.grade_level).count()
random_student = Student.objects.all()[randint(0, count - 1)] #single random object
#if that student isn't in list of already selected students
if not random_student.id in already_selected:
#create a passing progress report with the end date of that instructional cycle
Progress_Report.objects.create(date=cycle.date_finished, student=random_student, standard_mastered=standard, mastery_status=True)
#add that student to list of already selected students
already_selected.append(random_student.id)
This ends with the following error:
django.db.utils.IntegrityError: UNIQUE constraint failed:
student_progress_progress_report.standard_mastered_id
The progress_report table that I'm trying to fill is empty. I can add records to it using the admin interface. So I'm not sure where to look to fix my issue, because I'm not really sure what the problem is. Thanks for looking and any tips that you can provide. -- GH
Here are the models:
from django.db import models
from django.urls import reverse
gradeLevels = ((6,6), (7,7),(8,8),(9,9), (10,10), (11,11), (12,12))
subjects = (('Literacy','Literacy'), ('Math','Math'),
('Science','Science'), ('Social Studies','Social Studies'))
class Student(models.Model):
student_id = models.CharField(max_length=8, unique=True)
last_name = models.CharField(max_length=100)
first_name = models.CharField(max_length=100)
grade_level = models.IntegerField(choices=gradeLevels)
active_status = models.BooleanField(default=True)
class Meta:
ordering = ['grade_level', 'last_name']
def __str__(self):
#Return a string representation of the model.
return self.student_id + ' ' + self.last_name + ', ' + self.first_name
def student_name(self):
return self.last_name + ', ' + self.first_name
def get_absolute_url(self):
return reverse('student_progress:student_detail', args=[str(self.id)])
class Standard(models.Model):
subject = models.CharField(max_length=14, choices=subjects)
grade_level = models.IntegerField(choices=gradeLevels)
descriptor = models.CharField(max_length=15)
description = models.TextField()
essential_status = models.BooleanField(default=False)
class Meta:
ordering = ["subject", "grade_level", "descriptor"]
def __str__(self):
return self.descriptor + ': ' + self.description[:100]
def get_absolute_url(self):
return reverse('student_progress:standard_detail', args=[str(self.id)])
class Milestone (models.Model):
step_number = models.IntegerField()
statement = models.CharField(max_length=250, default="I can ...")
standard = models.ForeignKey(Standard, on_delete=models.CASCADE,
related_name='milestones', null=True, blank=True)
def __str__(self):
return str(self.step_number) + ': ' + self.statement[:50]
class Progress_Report(models.Model):
date = models.DateField(null=True)
student = models.OneToOneField(Student, on_delete=models.CASCADE)
standard_mastered = models.OneToOneField(Standard,
on_delete=models.CASCADE)
mastery_status = models.BooleanField(default=True)
class Meta:
ordering = ["date", "student"]
def __str__(self):
return self.date
class Instructional_Cycle(models.Model):
date_started = models.DateField(blank=False)
date_finished = models.DateField(blank=False)
standards = models.ManyToManyField(Standard, related_name="standards")
class Meta:
ordering = ['date_started']
def __str__(self):
return str(self.date_started) + ' to ' + str(self.date_finished)
def get_absolute_url(self):
return reverse('student_progress:cycle_detail', args=[str(self.id)])
