English 中文(简体)
Django模型 D. 高档检查 廉正
原标题:Django models Don t check fields Integrity

审议以下模式

class Faculty(models.Model):
     name = models.CharField(max_length=255)
     short_name = models.CharField(max_length=15)
     description = models.CharField(max_length=512)
     logo = models.ImageField(upload_to=faculty_upload_to, null=True)

That I do Faculty.objects.create() Or

faculty = Faculty()
faculty.save()

这就造成了数据库中的空档。

>>> from universities.models import *
>>> Faculty.objects.create()
<Faculty: Faculty object (2)>

why django doesn t give me an integrity error. I use django 5.0

问题回答

如果你没有具体说明外地的价值,那么Django就认为它,因为你正在为外地制造空洞的物体,而另一个员额则称:。 Don t允许在模型属性()上进行空洞的扼杀,但仅指明实地的属性,是无法告诉Django,以检查空洞。 您要么需要人工实地检查,要么可以凌驾于cleansaves in Django的models.Model的类别,即:

from django.db import models
from django.db import IntegrityError

class Faculty(models.Model):
    name = models.CharField(max_length=255)
    short_name = models.CharField(max_length=15)
    description = models.CharField(max_length=512)
    logo = models.ImageField(upload_to=faculty_upload_to, null=True)

    def clean(self):
        if self.name ==    or self.short_name ==    or self.description ==   :
            raise IntegrityError( No empty string allowed. )
    
    def save(self, *args, **kwargs):
        self.full_clean()
        super().save(*args, **kwargs)

References: Django object validation and Django IntegrityError

您可考虑增加CheckConstraint。 如果你想要在数据库一级验证价值:

class Faculty(models.Model):
    name = models.CharField(max_length=255)
    short_name = models.CharField(max_length=15)
    description = models.CharField(max_length=512)
    logo = models.ImageField(upload_to=faculty_upload_to, null=True)


    class Meta:
        constraints = [
            models.CheckConstraint(check=~Q(name="")),
            models.CheckConstraint(check=~Q(short_name="")),
            models.CheckConstraint(check=~Q(description="")),
        ]




相关问题
Can Django models use MySQL functions?

Is there a way to force Django models to pass a field to a MySQL function every time the model data is read or loaded? To clarify what I mean in SQL, I want the Django model to produce something like ...

An enterprise scheduler for python (like quartz)

I am looking for an enterprise tasks scheduler for python, like quartz is for Java. Requirements: Persistent: if the process restarts or the machine restarts, then all the jobs must stay there and ...

How to remove unique, then duplicate dictionaries in a list?

Given the following list that contains some duplicate and some unique dictionaries, what is the best method to remove unique dictionaries first, then reduce the duplicate dictionaries to single ...

What is suggested seed value to use with random.seed()?

Simple enough question: I m using python random module to generate random integers. I want to know what is the suggested value to use with the random.seed() function? Currently I am letting this ...

How can I make the PyDev editor selectively ignore errors?

I m using PyDev under Eclipse to write some Jython code. I ve got numerous instances where I need to do something like this: import com.work.project.component.client.Interface.ISubInterface as ...

How do I profile `paster serve` s startup time?

Python s paster serve app.ini is taking longer than I would like to be ready for the first request. I know how to profile requests with middleware, but how do I profile the initialization time? I ...

Pragmatically adding give-aways/freebies to an online store

Our business currently has an online store and recently we ve been offering free specials to our customers. Right now, we simply display the special and give the buyer a notice stating we will add the ...

Converting Dictionary to List? [duplicate]

I m trying to convert a Python dictionary into a Python list, in order to perform some calculations. #My dictionary dict = {} dict[ Capital ]="London" dict[ Food ]="Fish&Chips" dict[ 2012 ]="...

热门标签