django - Django 迁移 sqlmigrate

Question

我创建了一个迁移文件来更改模型的唯一键约束，以前它在唯一键中有 4 个字段，现在它有 5 个，在运行 migrate 命令后它工作正常。但现在我无法使用 sqlmigrate 生成 sql 查询。

错误是

“ValueError：发现规则集（business_function_id，business_process_id，process_state，status）的约束数量错误（0）”

在我的数据库中，现在的约束是：-

唯一键rule_set_business_function_id_bus_6bda6da3_uniq( business_function_id, business_process_id, process_state, rule_set_name, status),

我做错了什么？

以前的迁移

migrations.CreateModel(
        name='RuleSet',
        fields=[
            ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
            ('created_at', myghanta.fields.MysqlTimeStampField(auto_now_add=True, help_text='Date and Time of creation')),
            ('updated_at', myghanta.fields.MysqlTimeStampField(auto_now=True, help_text='Date and Time of modification')),
            ('process_state', models.CharField(max_length=255)),
            ('rule_set_name', models.CharField(max_length=255)),
            ('rule_set_link', models.URLField(max_length=400)),
            ('status', models.IntegerField(blank=True, choices=[(0, 'Created'), (1, 'Loaded'), (3, 'Validated'), (5, 'InActive'), (None, 'Deleted'), (2, 'Published')], null=True)),
            ('last_status', models.IntegerField(choices=[(0, 'Created'), (1, 'Loaded'), (3, 'Validated'), (5, 'InActive'), (None, 'Deleted'), (2, 'Published')], default=0)),
            ('curr_index_name', models.CharField(max_length=255, null=True)),
            ('prev_index_name', models.CharField(max_length=255, null=True)),
            ('version', models.PositiveIntegerField(default=0, null=True)),
            ('published_version', models.PositiveIntegerField(default=0, null=True)),
            ('published_date', myghanta.fields.MysqlTimeStampField(blank=True, help_text='Date and Time of ruleset last published', null=True)),
            ('marked_unpublished', models.BooleanField(default=False)),
            ('business_function', models.ForeignKey(null=True, on_delete=django.db.models.deletion.PROTECT, to='business.BusinessFunction')),
            ('business_process', models.ForeignKey(on_delete=django.db.models.deletion.PROTECT, to='business.BusinessProcess')),
            ('updated_by', models.ForeignKey(null=True, on_delete=django.db.models.deletion.PROTECT, related_name='last_updated', to=settings.AUTH_USER_MODEL)),
        ],
        options={
            'verbose_name': 'Rule Set',
            'verbose_name_plural': 'Rule Sets',
            'db_table': 'rule_set',
            'unique_together': {('business_function', 'business_process', 'process_state', 'status')},
        },
    )

新的迁移文件

class Migration(migrations.Migration):

dependencies = [
    ('business', '0001_initial'),
    ('rules', '0002_auto_20200914_1227'),
]

operations = [
    migrations.AlterUniqueTogether(
        name='ruleset',
        unique_together={('business_function', 'business_process', 'process_state', 'rule_set_name', 'status')},
    ),
]

追溯

    Traceback (most recent call last):
  File "manage.py", line 22, in <module>
    execute_from_command_line(sys.argv)
  File "/usr/local/lib/python3.7/site-packages/django/core/management/__init__.py", line 381, in execute_from_command_line
    utility.execute()
  File "/usr/local/lib/python3.7/site-packages/django/core/management/__init__.py", line 375, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/usr/local/lib/python3.7/site-packages/django/core/management/base.py", line 323, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/usr/local/lib/python3.7/site-packages/django/core/management/commands/sqlmigrate.py", line 30, in execute
    return super().execute(*args, **options)
  File "/usr/local/lib/python3.7/site-packages/django/core/management/base.py", line 364, in execute
    output = self.handle(*args, **options)
  File "/usr/local/lib/python3.7/site-packages/django/core/management/commands/sqlmigrate.py", line 64, in handle
    sql_statements = executor.collect_sql(plan)
  File "/usr/local/lib/python3.7/site-packages/django/db/migrations/executor.py", line 225, in collect_sql
    state = migration.apply(state, schema_editor, collect_sql=True)
  File "/usr/local/lib/python3.7/site-packages/django/db/migrations/migration.py", line 124, in apply
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File "/usr/local/lib/python3.7/site-packages/django/db/migrations/operations/models.py", line 530, in database_forwards
    getattr(new_model._meta, self.option_name, set()),
  File "/usr/local/lib/python3.7/site-packages/django/db/backends/base/schema.py", line 363, in alter_unique_together
    self._delete_composed_index(model, fields, {'unique': True}, self.sql_delete_unique)
  File "/usr/local/lib/python3.7/site-packages/django/db/backends/mysql/schema.py", line 84, in _delete_composed_index
    return super()._delete_composed_index(model, fields, *args)
  File "/usr/local/lib/python3.7/site-packages/django/db/backends/base/schema.py", line 397, in _delete_composed_index
    ", ".join(columns),
ValueError: Found wrong number (0) of constraints for rule_set(business_function_id, business_process_id, process_state, status)

标签： djangodjango-migrations