Django 模型 Meta models.CheckConstraint 定义约束中 使用中文 migrate报错:

Question

模型:

class Person(models.Model):
    name = models.CharField(max_length=10)
    old = models.PositiveSmallIntegerField()
    sex = models.BooleanField()

    class Meta:
        constraints = [
            models.CheckConstraint(check=~models.Q(name__startswith='谢, name='test_name'),
            ]

数据库使用：** PostgreSQL **

数据库 \encoding : UTF8

Settings中关于语言、地区设置：

LANGUAGE_CODE = 'zh-hans'

TIME_ZONE = 'Asia/Shanghai'

USE_I18N = True

USE_L10N = True

USE_TZ = False

migrete 同步数据库就会 报以下错误:

Operations to perform:
  Apply all migrations: admin, auth, contenttypes, sessions, test_app, test_database
Running migrations:
  Applying test_database.0001_initial...Traceback (most recent call last):
  File "manage.py", line 21, in <module>
    main()
  File "manage.py", line 17, in main
    execute_from_command_line(sys.argv)
  File "E:\StudyPython2020\venv\lib\site-packages\django\core\management\__init__.py", line 401, in execute_from_command_line
    utility.execute()
  File "E:\StudyPython2020\venv\lib\site-packages\django\core\management\__init__.py", line 395, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "E:\StudyPython2020\venv\lib\site-packages\django\core\management\base.py", line 328, in run_from_argv
    self.execute(*args, **cmd_options)
  File "E:\StudyPython2020\venv\lib\site-packages\django\core\management\base.py", line 369, in execute
    output = self.handle(*args, **options)
  File "E:\StudyPython2020\venv\lib\site-packages\django\core\management\base.py", line 83, in wrapped
    res = handle_func(*args, **kwargs)
  File "E:\StudyPython2020\venv\lib\site-packages\django\core\management\commands\migrate.py", line 233, in handle
    fake_initial=fake_initial,
  File "E:\StudyPython2020\venv\lib\site-packages\django\db\migrations\executor.py", line 117, in migrate
    state = self._migrate_all_forwards(state, plan, full_plan, fake=fake, fake_initial=fake_initial)
  File "E:\StudyPython2020\venv\lib\site-packages\django\db\migrations\executor.py", line 147, in _migrate_all_forwards
    state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial)
  File "E:\StudyPython2020\venv\lib\site-packages\django\db\migrations\executor.py", line 245, in apply_migration
    state = migration.apply(state, schema_editor)
  File "E:\StudyPython2020\venv\lib\site-packages\django\db\migrations\migration.py", line 124, in apply
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File "E:\StudyPython2020\venv\lib\site-packages\django\db\migrations\operations\models.py", line 822, in database_forwards
    schema_editor.add_constraint(model, self.constraint)
  File "E:\StudyPython2020\venv\lib\site-packages\django\db\backends\base\schema.py", line 360, in add_constraint
    sql = constraint.create_sql(model, self)
  File "E:\StudyPython2020\venv\lib\site-packages\django\db\models\constraints.py", line 47, in create_sql
    check = self._get_check_sql(model, schema_editor)
  File "E:\StudyPython2020\venv\lib\site-packages\django\db\models\constraints.py", line 40, in _get_check_sql
    return sql % tuple(schema_editor.quote_value(p) for p in params)
  File "E:\StudyPython2020\venv\lib\site-packages\django\db\models\constraints.py", line 40, in <genexpr>
    return sql % tuple(schema_editor.quote_value(p) for p in params)
  File "E:\StudyPython2020\venv\lib\site-packages\django\db\backends\postgresql\schema.py", line 38, in quote_value
    return psycopg2.extensions.adapt(value).getquoted().decode()
UnicodeEncodeError: 'latin-1' codec can't encode character '\u8c22' in position 0: ordinal not in range(256)

难道说数据库约束不能使用中文?

问题解决： 在中文后使用 '谢'.encode('latin-1') 编码即可解决问题！

Answer 1

https://blog.csdn.net/weixin_33901641/article/details/93406413