Ticket #420 (closed defect: fixed)

Opened 4 years ago

Last modified 4 years ago

Field ordering wrong after running an initial schema migration

Reported by: jklaiho Owned by: andrew
Priority: major Milestone: 0.7.1
Component: commands Version: 0.7
Keywords: field ordering initial schemamigration Cc:


#145 dealt with incorrect field ordering, and was fixed quite a long time ago.

Since upgrading to South 0.7, we've been running into what seems to be the same problem, though manifesting itself in a different way.

Here's a sample model definition, a simple newsletter model:

    email = models.EmailField(unique=True)
    name = models.CharField(max_length=100, blank=True)
    date_added = models.DateTimeField(blank=True, null=True, editable=False)
    date_modified = models.DateTimeField(blank=True, null=True, editable=False)
    posts_received = models.PositiveIntegerField(default=0, editable=False)

Here's the frozen model definition produced for it by a schemamigration command with the --initial parameter:

models = {
        'simplenewsletter.recipient': {
            'Meta': {'object_name': 'Recipient'},
            'date_added': ('django.db.models.fields.DateTimeField', [], {'null': 'True', 'blank': 'True'}),
            'date_modified': ('django.db.models.fields.DateTimeField', [], {'null': 'True', 'blank': 'True'}),
            'email': ('django.db.models.fields.EmailField', [], {'unique': 'True', 'max_length': '75'}),
            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
            'name': ('django.db.models.fields.CharField', [], {'max_length': '100', 'blank': 'True'}),
            'posts_received': ('django.db.models.fields.PositiveIntegerField', [], {'default': '0'})

It looks like the frozen fields are listed in alphabetical order instead of the model order. Doesn't seem right, but may be intentional. But the real weirdness is the field ordering as produced by running that migration:


The final ordering doesn't correspond to either the way it's set in the model, or the frozen dictionary in the migration.

This is very inconvenient when using GUI tools like Sequel Pro to browse and administer the database. Often-crucial id fields may be practically anywhere and not the first in the list of fields, as they are supposed to (and were with South 0.6). "Less-important" fields being in the wrong order is also a hassle when trying to locate things.

We're using MySQL 5.1.37, the pre-1.2 trunk version of Django and database collation utf8_swedish_ci.

Change History

comment:1 Changed 4 years ago by jklaiho

Ahh, I see where the final ordering comes from, it's in the actual table creation command in the migration:

db.create_table('simplenewsletter_recipient', (
            ('posts_received', self.gf('django.db.models.fields.PositiveIntegerField')(default=0)),
            ('name', self.gf('django.db.models.fields.CharField')(max_length=100, blank=True)),
            ('date_modified', self.gf('django.db.models.fields.DateTimeField')(null=True, blank=True)),
            ('email', self.gf('django.db.models.fields.EmailField')(unique=True, max_length=75)),
            ('date_added', self.gf('django.db.models.fields.DateTimeField')(null=True, blank=True)),
            ('id', self.gf('django.db.models.fields.AutoField')(primary_key=True)),

Still, the fields listed in that command don't correspond to the actual model or the frozen version as listed in the ticket.

comment:2 Changed 4 years ago by brian@…

BaseChanges? class is using a regular dict instead of a SortedDict?().

I fixed it as following,

On /south/creator/changes.py

from django.utils.datastructures import SortedDict?

class BaseChanges?(object):

def split_model_def(self, model, model_def):

real_fields = SortedDict?()
meta = SortedDict?()
m2m_fields = SortedDict?()

comment:3 Changed 4 years ago by brian@…

I got few other errors if I use SortedDict? on the meta dict. I guess I should use Sorted Dict on real_fields only.

comment:4 Changed 4 years ago by andrew

  • Status changed from new to assigned

Marked #455 as a dupe of this.

comment:5 Changed 4 years ago by andrew

  • Status changed from assigned to closed
  • Resolution set to fixed

Seems to have been fixed at some point since this was reported. My subconscious is clearly better at bugtrackers than me.

comment:6 Changed 4 years ago by egmanoj@…

I downloaded 0.7.1 and the error is still apparent. Does the trunk version have a fix?

comment:7 Changed 4 years ago by andrew

The fix for this is supposedly in 0.7.1, yes - if it's still happening for you, could you attach examples of the model definition and resulting create_table call?

Note: See TracTickets for help on using tickets.