Python MySQL:django.db.utils.OperationalError:（1366，“不正确的整数值：'；类别对象'；用于第1行的列'；类别id'”）

在Django中使用MySQL，我将模型从使用字符串作为“category”更改为使用FK。它现在已被损坏

django.db.utils.OperationalError: (1366, "Incorrect integer value: 'Category object' for column 'category_id' at row 1")

起初，它看起来像：

class ItemRecord(models.Model):
    catalog_id = models.IntegerField()
    name = models.CharField(max_length=250)
    price = models.DecimalField(max_digits=7, decimal_places=2)
    active = models.BooleanField(default=True) # is the item being sold at all? (carried)
    in_stock = models.BooleanField(default=True) # is the item currently in stock?
    banned = models.BooleanField(default=False)
    category = models.CharField(max_length=250, null=True, blank=True)

    class Meta:
        abstract = True


class FermentableRecord(ItemRecord):#record of each item
    pass

class HopRecord(ItemRecord):
    pass

class YeastRecord(ItemRecord):
    pass

然后，我使用FK：

class Category(models.Model):
    name = models.CharField(max_length=250)
    banned = models.BooleanField(default=False)


class ItemRecord(models.Model):
    catalog_id = models.IntegerField()
    name = models.CharField(max_length=250)
    price = models.DecimalField(max_digits=7, decimal_places=2)
    active = models.BooleanField(default=True) # is the item being sold at all? (carried)
    in_stock = models.BooleanField(default=True) # is the item currently in stock?
    banned = models.BooleanField(default=False)
    category = models.ForeignKey(Category, related_name="items")

    class Meta:
        abstract = True


class FermentableRecord(ItemRecord):#record of each item
    pass

class HopRecord(ItemRecord):
    pass

class YeastRecord(ItemRecord):
    pass

这与在3种不同的记录模型上使用相同的相关名称不同。 接下来我有：

class Category(models.Model):
    name = models.CharField(max_length=250)
    banned = models.BooleanField(default=False)


class ItemRecord(models.Model):
    catalog_id = models.IntegerField()
    name = models.CharField(max_length=250)
    price = models.DecimalField(max_digits=7, decimal_places=2)
    active = models.BooleanField(default=True) # is the item being sold at all? (carried)
    in_stock = models.BooleanField(default=True) # is the item currently in stock?
    banned = models.BooleanField(default=False)

    class Meta:
        abstract = True


class FermentableRecord(ItemRecord):#record of each item
    category = models.ForeignKey(Category, related_name="fermentable_items", null=True, blank=True)

class HopRecord(ItemRecord):
    category = models.ForeignKey(Category, related_name="hops_items", null=True, blank=True)

class YeastRecord(ItemRecord):
    category = models.ForeignKey(Category, related_name="yeast_items", null=True, blank=True)

现在我有：

class Category(models.Model):
    name = models.CharField(max_length=250)
    banned = models.BooleanField(default=False)


class ItemRecord(models.Model):
    catalog_id = models.IntegerField()
    name = models.CharField(max_length=250)
    price = models.DecimalField(max_digits=7, decimal_places=2)
    active = models.BooleanField(default=True) # is the item being sold at all? (carried)
    in_stock = models.BooleanField(default=True) # is the item currently in stock?
    banned = models.BooleanField(default=False)
    category = models.CharField(max_length=250, null=True, blank=True)

    class Meta:
        abstract = True


class FermentableRecord(ItemRecord):#record of each item
    pass

class HopRecord(ItemRecord):
    pass

class YeastRecord(ItemRecord):
    pass

---

我可以

makemigrations

，但我甚至无法连接到数据库。我只想重置数据库，因为它正在开发中，但我什么也做不了。

category

字段是一个字符串，然后我将其设置为FK，在清除现有字符串值（由于错误，所有“category object”都在该字符串中）之前，它需要一个int。

是否检查了category object表中是否存在category，id最初存储在category字段中

例如：id=1366的类别对象存在

Category.objects.filter(id=1366).exists()

---

如果您只想删除类别中的数据，则可以在shell中执行以下操作：

$ python manage.py dbshell # this will start the mysql client
mysql> show tables likes '%_itemrecord'; -- find the table name
mysql> update XXX_itemrecord set category=null; -- this will set all category values to NULL so that you can migrate to FK 

$ python manage.py migrate app_name zero # this will blow away all your current data
$ python manage.py migrate app_name 

如果您不介意丢失数据，并且应用程序名为app_name，则可以在shell中执行以下操作：

$ python manage.py dbshell # this will start the mysql client
mysql> show tables likes '%_itemrecord'; -- find the table name
mysql> update XXX_itemrecord set category=null; -- this will set all category values to NULL so that you can migrate to FK 

$ python manage.py migrate app_name zero # this will blow away all your current data
$ python manage.py migrate app_name 

---

“但我甚至连数据库都无法连接。”请解释一下。如果无法连接到数据库，如何进行迁移？它不会迁移，我的意思是它只进行迁移