title: Django does not let me update simple model to sqlite DB
body: <p>I'm currently trying to get familiarized with django and I got stuck with an error I can't fix. My django version is 1.7a2 (from developer).</p>
  
  <p>My model is quite simple:</p>
  
  <pre><code>from django.db import models
  
  class dataset(models.Model):
      ID = models.CharField("ID of current dataset", max_length=20, primary_key=True)
      date = models.DateTimeField('Date of current dataset')
      name = models.CharField("Name of current dataset", max_length=20)
      value = models.FloatField("Value of current dataset")
  </code></pre>
  
  <p>But when I run 'python manage.py syncdb' command for the second time I get this error:</p>
  
  <pre><code>$ python manage.py syncdb
  Operations to perform:
    Synchronize unmigrated apps: admin, contenttypes, auth, sessions
    Apply all migrations: display
  Synchronizing apps without migrations:
    Creating tables...
    Installing custom SQL...
    Installing indexes...
  Running migrations:
    Applying display.0001_initial...Traceback (most recent call last):
    File "manage.py", line 10, in &lt;module&gt;
      execute_from_command_line(sys.argv)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/core/management/__init__.py", line 427, in execute_from_command_line
      utility.execute()
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/core/management/__init__.py", line 419, in execute
      self.fetch_command(subcommand).run_from_argv(self.argv)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/core/management/base.py", line 287, in run_from_argv
      self.execute(*args, **options.__dict__)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/core/management/base.py", line 336, in execute
      output = self.handle(*args, **options)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/core/management/base.py", line 531, in handle
      return self.handle_noargs(**options)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/core/management/commands/syncdb.py", line 22, in handle_noargs
      call_command("migrate", **options)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/core/management/__init__.py", line 167, in call_command
      return klass.execute(*args, **defaults)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/core/management/base.py", line 336, in execute
      output = self.handle(*args, **options)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/core/management/commands/migrate.py", line 145, in handle
      executor.migrate(targets, plan, fake=options.get("fake", False))
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/db/migrations/executor.py", line 60, in migrate
      self.apply_migration(migration, fake=fake)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/db/migrations/executor.py", line 94, in apply_migration
      migration.apply(project_state, schema_editor)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/db/migrations/migration.py", line 97, in apply
      operation.database_forwards(self.app_label, schema_editor, project_state, new_state)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/db/migrations/operations/models.py", line 28, in database_forwards
      schema_editor.create_model(model)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/db/backends/schema.py", line 253, in create_model
      self.execute(sql, params)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/db/backends/schema.py", line 95, in execute
      cursor.execute(sql, params)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/db/backends/utils.py", line 77, in execute
      return super(CursorDebugWrapper, self).execute(sql, params)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/db/backends/utils.py", line 61, in execute
      return self.cursor.execute(sql, params)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/db/utils.py", line 93, in __exit__
      six.reraise(dj_exc_type, dj_exc_value, traceback)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/db/backends/utils.py", line 61, in execute
      return self.cursor.execute(sql, params)
    File "/usr/local/lib/python2.7/dist-packages/django-trunk/django/db/backends/sqlite3/base.py", line 475, in execute
      return Database.Cursor.execute(self, query, params)
  django.db.utils.OperationalError: duplicate column name: ID
  </code></pre>
  
  <p>Does anyone have any idea what I am doing wrong?</p>
  
  <p>Thanks in advance.</p>