Django overriding model save method sets unspecified fields to NULL

Question

Explanation

I have an extension of my model in eiysTblModels because we are using inspectdb option of django manage.py. Since it overwrites the models.py,we do not touch models.py, instead write our extensions to eiysTblModels.

Problem

Anyway, when I call edit_group function, it sets the slug and dates correctly as specified but it overwrites the other fields such as is_active, isapproved etc to NULL, which are initially set to 1.

vieys.py

def edit_group(request,group_id):

    groupinfo = request.POST

    group = eiysTblGroup(id = group_id )
    group.name = groupinfo.get('group-name','')

    group.save()

eiysTblModels.py

class eiysTblGroup(TblGroup):
class Meta:
    proxy = True
def save(self, *args, **kwargs):
    self.slug = slugify(self.name)
    if not self.id:
        self.date_created = datetime.now().strftime('%Y-%m-%d %H:%M:%S')
        self.isactive = 1
    self.date_last_modified = datetime.now().strftime('%Y-%m-%d %H:%M:%S')
    super(TblGroup, self).save(*args, **kwargs)

models.py

class TblGroup(models.Model):
    id = models.IntegerField(primary_key=True)
    name = models.CharField(max_length=250, blank=True)
    date_created = models.DateTimeField(blank=True, null=True)
    date_last_modified = models.DateTimeField(blank=True, null=True)
    creator = models.ForeignKey(AuthUser, blank=True, null=True)
    group_photo_url = models.CharField(max_length=250, blank=True)
    isactive = models.IntegerField(blank=True, null=True)
    slug = models.CharField(max_length=250, blank=True)
    code = models.IntegerField(blank=True, null=True)
    class Meta:
        managed = False
        db_table = 'tbl_group'

Summary

Basically, what I need is to automatically update date_last_modified, date_created and slug when I save them, and do NOT update any other part to NULL.

score 1 · Answer 1 · answered Nov 03 '15 at 11:29

1

Obviously, my erroneous part is this in view:

group = eiysTblGroup(id = group_id )

I'm not sure how I made such a silly mistake. The correct form should be:

group = eiysTblGroup.objects.get(id = group_id )

Then it works correctly...

answered Nov 03 '15 at 11:29

Umut Akın

45
1
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score 0 · Accepted Answer · edited May 23 '17 at 12:23

0

I believe the answer for your question can be found here:

Automatic creation date for django model form objects?

You want to use those, because Django can set creation and modification dates for you automatically without any additional interactions needed.

models.DateTimeField(auto_now_add=True)
models.DateTimeField(auto_now=True)

As for the slug, shorten your save() method to:

def save(self, *args, **kwargs):
    self.slug = slugify(self.name)
    super(eiysTblGroup, self).save(*args, **kwargs)

edited May 23 '17 at 12:23

Community

1
1

answered Nov 03 '15 at 11:02

Nhor

3,860
6
28
41

Thank you for the fast response, but I would like to set the slug too, and maybe I will be required to do more changes in the future if necessary. – Umut Akın Nov 03 '15 at 11:04
i updated the answer with the slug as well. hope it helps! – Nhor Nov 03 '15 at 11:13

Django overriding model save method sets unspecified fields to NULL

2 Answers2