1.在app/models建立一个moment定义信息发布表

from django.db import models

# Create your models here.

class Moment(models.Model):
    content=models.CharField(max_length=300)
    user_name = models.CharField(max_length=20)


    kind = models.CharField(max_length=20)

分别执行下面

python manage.py makemigrations app

修改了一下content的长度 200=300

再次执行

python manage.py makemigrations app

执行python manage.py migrate 移植到数据库

appledeMacBook-Pro-3:py3DjangoSite apple$ python manage.py makemigrations app
Migrations for 'app':
app/migrations/0001_initial.py
- Create model Moment
appledeMacBook-Pro-3:py3DjangoSite apple$ python manage.py makemigrations app
Migrations for 'app':
app/migrations/0002_auto_20191223_0716.py
- Alter field content on moment
appledeMacBook-Pro-3:py3DjangoSite apple$ python manage.py migrate
Operations to perform:
Apply all migrations: admin, app, auth, contenttypes, sessions
Running migrations:
Applying contenttypes.0001_initial... OK
Applying auth.0001_initial... OK
Applying admin.0001_initial... OK
Applying admin.0002_logentry_remove_auto_add... OK
Applying admin.0003_logentry_add_action_flag_choices... OK
Applying app.0001_initial... OK
Applying app.0002_auto_20191223_0716... OK
Applying contenttypes.0002_remove_content_type_name... OK
Applying auth.0002_alter_permission_name_max_length... OK
Applying auth.0003_alter_user_email_max_length... OK
Applying auth.0004_alter_user_username_opts... OK
Applying auth.0005_alter_user_last_login_null... OK
Applying auth.0006_require_contenttypes_0002... OK
Applying auth.0007_alter_validators_add_error_messages... OK
Applying auth.0008_alter_user_username_max_length... OK
Applying auth.0009_alter_user_last_name_max_length... OK
Applying auth.0010_alter_group_name_max_length... OK
Applying auth.0011_update_proxy_permissions... OK
Applying sessions.0001_initial... OK