django学习笔记【004】创建带有model的app

第一步：配置连接字符串

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': 'tempdb',
        'HOST': '127.0.0.1',
        'USER': 'appuser',
        'PORT': '3306',
        'PASSWORD': '123456'
    }
}

第二步：定义模式

from django.db import models

# Create your models here.
class Question(models.Mode):
    question_text = models.CharField(max_length=200)
    pub_date = models.DateTimeField('date published')

class Choice(models.Model):
    question = models.ForeignKey(Question, on_delete=models.CASCADE) 
    choice_text = models.CharField(max_length=200)
    votes = models.IntegerField(default=0)

第三步：激活模式

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'polls.apps.PollsConfig', #把app注册到django就算是激活模式了
]

第四步：通知django你已经对模式做了变更

python3.5 manage.py makemigrations polls
Migrations for 'polls':
  polls/migrations/0001_initial.py:
    - Create model Choice
    - Create model Question
    - Add field question to choice

第五步：把模式的变更迁移到mysql数据库

Operations to perform:
  Apply all migrations: admin, auth, contenttypes, polls, 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 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 polls.0001_initial... OK
  Applying sessions.0001_initial... OK

第六步：查看数据库的生成的表

show tables;
+----------------------------+
| Tables_in_tempdb           |
+----------------------------+
| auth_group                 |
| auth_group_permissions     |
| auth_permission            |
| auth_user                  |
| auth_user_groups           |
| auth_user_user_permissions |
| django_admin_log           |
| django_content_type        |
| django_migrations          |
| django_session             |
| polls_choice               |
| polls_question             |
+----------------------------+

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