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Python Using Databases in Python Meet Peewee Queries Are Your Friend

Not getting IntegrityError

here's my code, it's mostly like his, especially that username is unique:

#!/usr/bin/env python3
# encoding: utf-8

from peewee import *

db = SqliteDatabase("students.db")


class Student(Model):

    # no username -> error
    username = CharField(max_length=255, unique=True)
    points = IntegerField(default=0)

    class Meta:
        database = db


students = [
    {"username": "dmr",
     "points": 4888},
    {"username": "ken",
     "points": 420},
    {"username": "sc3",
     "points": 34},
]


def add_students():
    for student in students:
        try:
            Student.create(username=student["username"],
                       points=student["points"])
        except IntegrityError:
            student_record = Student.get(username=student["username"])
            student_record.points = student["points"]
            student_record.save()


if __name__ == "__main__":
    db.connect()
    db.create_tables([Student], safe=True)
    add_students()

But every time I run the program it creates three new rows. Any idea why?

EDIT 0: I tried using the code from the lesson and it didn't throw an IntegrityError either. So it's not my code, apparently.

1 Answer

Marek Zakrzewski
Marek Zakrzewski
2,920 Points

Had the same issue, turned out that I just forgot to save the code, before running the file.