Question

models.py

from __future__ import unicode_literals
from django.core.urlresolvers import reverse
from django.db import models
from django.utils.text import slugify


class Post(models.Model):
    title = models.CharField(max_length = 120)
    image = models.ImageField(null=True,blank=True)
    draft  = models.BooleanField(default=False)
    publish = models.DateField(auto_now=False, auto_now_add=False)
    Updated = models.DateTimeField(auto_now=True,auto_now_add=False)
    Timestamp = models.DateTimeField(auto_now=False,auto_now_add=True)

    def __unicodde__(self):
        return self.Title

    def __str__(self):
        return self.title

    def get_absolute_url(self):
        #return 'posts/%s/' %(self.id)
        return reverse('posts:detail', kwargs={'id':self.id})
    class Meta:
        ordering = ["-Timestamp","Updated"]

forms.py

from django import forms
from .models import Post

class PostForm(forms.ModelForm):
    class Meta:
        model = Post
        fields = [
                        "title",
                        "Content",
                        "image",
                        "draft",
                        "publish",

        ]

和终端：

    jayu@broadwell-gt2:~/Desktop/trydjango19$ python manage.py migrate
    Operations to perform:
      Apply all migrations: admin, contenttypes, posts, auth, sessions
    Running migrations:
      Rendering model states... DONE
      Applying posts.0002_auto_20180526_0745...Traceback (most recent call last):
      File "manage.py", line 10, in <module>
        execute_from_command_line(sys.argv)
      File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 350, in execute_from_command_line
        utility.execute()
      File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 342, in execute
        self.fetch_command(subcommand).run_from_argv(self.argv)
      File "/usr/local/lib/python2.7/dist-packages/django/core/management/base.py", line 348, in run_from_argv
        self.execute(*args, **cmd_options)
      File "/usr/local/lib/python2.7/dist-packages/django/core/management/base.py", line 399, in execute
        output = self.handle(*args, **options)
/migration.py", line 123, in apply
        operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
      File "/usr/local/lib/python2.7/dist-packages/django/db/migrations/operations/fields.py", line 62, in database_forwards
        field,
      File "/usr/local/lib/python2.7/dist-packages/django/db/backends/sqlite3/schema.py", line 221, in add_field
        self._remake_table(model, create_fields=[field])
      File "/usr/local/lib/python2.7/dist-packages/django/db/backends/sqlite3/schema.py", line 103, in _remake_table
        self.effective_default(field)
      File "/usr/local/lib/python2.7/dist-packages/django/db/backends/base/schema.py", line 210, in effective_default
        default = field.get_db_prep_save(default, self.connection)
      File "/usr/local/lib/python2.7/dist-packages/django/db/models/fields/__init__.py", line 728, in get_db_prep_save
        prepared=False)
      File "/usr/local/lib/python2.7/dist-packages/django/db/models/fields/__init__.py", line 1301, in get_db_prep_value
        value = self.get_prep_value(value)
      File "/usr/local/lib/python2.7/dist-packages/django/db/models/fields/__init__.py", line 1296, in get_prep_value
        return self.to_python(value)
      File "/usr/local/lib/python2.7/dist-packages/django/db/models/fields/__init__.py", line 1260, in to_python
        parsed = parse_date(value)
      File "/usr/local/lib/python2.7/dist-packages/django/utils/dateparse.py", line 60, in parse_date
        match = date_re.match(value)
    TypeError: expected string or buffer

成功完成python manage.py makemigrations后，

当我尝试迁移时

TypeError：期望的字符串或缓冲区发生错误。

我在数据类型上做过任何错误或其他错误吗？

我在这里做错了什么？

请帮帮我......

模型字段中的任何默认值出错？

Answer 1

我认为django docs关于DateTimeField的引用可以帮到你：

选项auto_now_add，auto_now和default是互斥的。这些选项的任何组合都会导致错误。

TypeError：尝试迁移数据库时的预期字符串或缓冲区

1 个答案: