MinMaxValidator

Description

This check verifies that IntegerField and DecimalField instances have both MinValueValidator and MaxValueValidator to ensure data consistency and prevent out-of-range values from being stored in the database.

Rationale

Using MinValueValidator and MaxValueValidator for numeric fields helps maintain data integrity by enforcing minimum and maximum allowed values for the fields. This reduces the chance of storing out-of-range values and helps maintain a consistent data set.

Example

Consider the following model:

from django.db import models

class Product(models.Model):
    name = models.CharField(max_length=100)
    price = models.DecimalField(max_digits=10, decimal_places=2)

The price field is a DecimalField without MinValueValidator and MaxValueValidator. The check would detect this and recommend adding the validators:

from django.core.validators import MinValueValidator, MaxValueValidator

class Product(models.Model):
    name = models.CharField(max_length=100)
    price = models.DecimalField(
        max_digits=10, decimal_places=2,
        validators=[MinValueValidator(0), MaxValueValidator(10000)]
    )

By using MinValueValidator and MaxValueValidator, you can ensure that the price field only accepts values within a specified range.