Django模型元更改在更改元属性时引发错误

Question

我有下面的Django模型，其中managed=False，现在我需要将其更改为managed=True，并添加一个属性选择的char字段 第1版

class TblHoldings(models.Model):
    item_code = models.CharField(unique=True, max_length=5)
    product_name = models.CharField(max_length=45)
    service_provider = models.ForeignKey(TblHoldingsServiceProviders,on_delete=models.CASCADE, related_name='service_provider',db_column='service_provider')
    account_details = models.CharField(max_length=100)
    purchase_cost = models.IntegerField()
    current_value = models.IntegerField()
    power_of = models.CharField(max_length=45, blank=True, null=True)
    purchase_date = models.DateTimeField(blank=True, null=True)
    updated_at = models.DateTimeField(blank=True, null=True)
    created_at = models.DateTimeField(blank=True, null=True)

    def __str__(self):
        return self.product_name + ' at ' + self.service_provider.provider_name

    class Meta:
        verbose_name = 'Holding'
        verbose_name_plural = 'Holdings'
        managed = False
        db_table = 'tbl_holdings'

第2版

FIN_GOAL_TERM =(
    ('L', 'Long Term 7+ years'),
    ('M', 'Medium Term 3-7 years'),
    ('S', 'Short Term <2 years'),
)
class TblHoldings(models.Model):
    item_code = models.CharField(unique=True, max_length=5)
    product_name = models.CharField(max_length=45)
    service_provider = models.ForeignKey(TblHoldingsServiceProviders,on_delete=models.CASCADE, related_name='service_provider',db_column='service_provider')
    account_details = models.CharField(max_length=100)
    purchase_cost = models.IntegerField()
    current_value = models.IntegerField()
    power_of = models.CharField(max_length=45, blank=True, null=True)
    purchase_date = models.DateTimeField(blank=True, null=True)
    goal_term = models.CharField(max_length=40, choices=FIN_GOAL_TERM)
    updated_at = models.DateTimeField(blank=True, null=True)
    created_at = models.DateTimeField(blank=True, null=True)

    def __str__(self):
        return self.product_name + ' at ' + self.service_provider.provider_name

    class Meta:
        verbose_name = 'Holding'
        verbose_name_plural = 'Holdings'
        managed = True
        db_table = 'tbl_holdings'

现在我在运行make migrations时遇到以下错误，有人能建议如何解决这个问题吗

File "/root/appstaq_fin/venv/lib/python3.6/site-packages/django/db/backends/base/schema.py", line 447, in add_field self.execute(sql, params) File "/root/appstaq_fin/venv/lib/python3.6/site-packages/django/db/backends/base/schema.py", line 137, in execute cursor.execute(sql, params) File "/root/appstaq_fin/venv/lib/python3.6/site-packages/django/db/backends/utils.py", line 99, in execute return super().execute(sql, params) File "/root/appstaq_fin/venv/lib/python3.6/site-packages/django/db/backends/utils.py", line 67, in execute return self._execute_with_wrappers(sql, params, many=False, executor=self._execute) File "/root/appstaq_fin/venv/lib/python3.6/site-packages/django/db/backends/utils.py", line 76, in _execute_with_wrappers return executor(sql, params, many, context) File "/root/appstaq_fin/venv/lib/python3.6/site-packages/django/db/backends/utils.py", line 84, in _execute return self.cursor.execute(sql, params) File "/root/appstaq_fin/venv/lib/python3.6/site-packages/django/db/utils.py", line 89, in exit raise dj_exc_value.with_traceback(traceback) from exc_value File "/root/appstaq_fin/venv/lib/python3.6/site-packages/django/db/backends/utils.py", line 84, in _execute return self.cursor.execute(sql, params) File "/root/appstaq_fin/venv/lib/python3.6/site-packages/django/db/backends/mysql/base.py", line 71, in execute return self.cursor.execute(query, args) File "/root/appstaq_fin/venv/lib/python3.6/site-packages/MySQLdb/cursors.py", line 209, in execute res = self._query(query) File "/root/appstaq_fin/venv/lib/python3.6/site-packages/MySQLdb/cursors.py", line 315, in _query db.query(q) File "/root/appstaq_fin/venv/lib/python3.6/site-packages/MySQLdb/connections.py", line 231, in query _mysql.connection.query(self, query) django.db.utils.OperationalError: (1060, "Duplicate column name 'power_of'")

Answer 1

因此，根据Daniel Roseman的建议，我运行了下面的命令，它解决了我的问题

python3 manage.py migrate fake