GeoDjango migrate giving the following error - ValueError: Cannot use object with type int for a spatial lookup parameter

Question

我正在尝试创建一个具有地理空间字段的模型。当我尝试迁移时，我收到以下错误：

  Apply all migrations: admin, auth, contenttypes, map, sessions
Running migrations:
  Applying map.0008_territorio_geometry...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 "C:\Users\Marco\Envs\um\lib\site-packages\django\core\management\__init__.py", line 401, in execute_from_command_line
    utility.execute()
  File "C:\Users\Marco\Envs\um\lib\site-packages\django\core\management\__init__.py", line 395, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "C:\Users\Marco\Envs\um\lib\site-packages\django\core\management\base.py", line 328, in run_from_argv
    self.execute(*args, **cmd_options)
  File "C:\Users\Marco\Envs\um\lib\site-packages\django\core\management\base.py", line 369, in execute
    output = self.handle(*args, **options)
  File "C:\Users\Marco\Envs\um\lib\site-packages\django\core\management\base.py", line 83, in wrapped
    res = handle_func(*args, **kwargs)
  File "C:\Users\Marco\Envs\um\lib\site-packages\django\core\management\commands\migrate.py", line 231, in handle
    post_migrate_state = executor.migrate(
  File "C:\Users\Marco\Envs\um\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 "C:\Users\Marco\Envs\um\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 "C:\Users\Marco\Envs\um\lib\site-packages\django\db\migrations\executor.py", line 245, in apply_migration
    state = migration.apply(state, schema_editor)
  File "C:\Users\Marco\Envs\um\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 "C:\Users\Marco\Envs\um\lib\site-packages\django\db\migrations\operations\fields.py", line 110, in database_forwards
    schema_editor.add_field(
  File "C:\Users\Marco\Envs\um\lib\site-packages\django\db\backends\base\schema.py", line 450, in add_field
    definition, params = self.column_sql(model, field, include_default=True)
  File "C:\Users\Marco\Envs\um\lib\site-packages\django\db\backends\base\schema.py", line 223, in column_sql
    default_value = self.effective_default(field)
  File "C:\Users\Marco\Envs\um\lib\site-packages\django\db\backends\base\schema.py", line 303, in effective_default
    return field.get_db_prep_save(self._effective_default(field), self.connection)
  File "C:\Users\Marco\Envs\um\lib\site-packages\django\db\models\fields\__init__.py", line 821, in get_db_prep_save
    return self.get_db_prep_value(value, connection=connection, prepared=False)
  File "C:\Users\Marco\Envs\um\lib\site-packages\django\contrib\gis\db\models\fields.py", line 147, in get_db_prep_value
    super().get_db_prep_value(value, connection, *args, **kwargs),
  File "C:\Users\Marco\Envs\um\lib\site-packages\django\db\models\fields\__init__.py", line 816, in get_db_prep_value
    value = self.get_prep_value(value)
  File "C:\Users\Marco\Envs\um\lib\site-packages\django\contrib\gis\db\models\fields.py", line 190, in get_prep_value
    raise ValueError('Cannot use object with type %s for a spatial lookup parameter.' % type(obj).__name__)
ValueError: Cannot use object with type int for a spatial lookup parameter.

我也尝试从我的模型中删除属性，但没有任何变化。以下是我的models.py

from django.contrib.gis.db import models

# Create your models here.
class Piano(models.Model):
    """Modello che rappresenta un piano"""
    titolo = models.CharField(max_length=100, help_text='Nome del piano')
    acronimo = models.CharField(max_length=100, help_text='Acronimo del piano')
    #fk_territorio = models.ForeignKey('Territorio', verbose_name='Territorio', on_delete=models.SET_NULL, null=True)

    def __str__(self):
        """String for representing the Model object."""
        return self.titolo

    class Meta:
        verbose_name_plural = "Piani"

class Territorio(models.Model):
    """Modello che rappresenta la tipologia di una norma"""
    nome = models.CharField(max_length=100, help_text='Nome del territorio')
    fk_tipo_territorio = models.ForeignKey('TipoTerritorio', verbose_name='Tipo Territorio', on_delete=models.SET_NULL, null=True)
    parent = models.ForeignKey('self', blank=True, related_name='child', help_text='Parent del Territorio', on_delete=models.SET_NULL, null=True)
    codice = models.PositiveIntegerField(help_text='Codice del Territorio', null=True)
    geometry = models.GeometryField(spatial_index=True, null=True)

    def __str__(self):
        """String for representing the Model object."""
        return self.nome

    class Meta:
        verbose_name_plural = "Territori"

class TipoTerritorio(models.Model):
    """Modello che rappresenta la tipologia di una norma"""
    nome = models.CharField(max_length=100, help_text='Tipologia di territorio')

    def __str__(self):
        """String for representing the Model object."""
        return self.nome

    class Meta:
        verbose_name_plural = "TipiTerritorio"

我对 Django 和 GeoDjango 比较陌生，我可能忽略了一些东西。关于如何解决迁移错误的任何想法？

编辑：添加了 0008_territorio_geometry.py

# Generated by Django 3.0.4 on 2020-04-06 13:19

import django.contrib.gis.db.models.fields
from django.db import migrations


class Migration(migrations.Migration):

    dependencies = [
        ('map', '0007_auto_20200406_1506'),
    ]

    operations = [
        migrations.AddField(
            model_name='territorio',
            name='geometry',
            field=django.contrib.gis.db.models.fields.GeometryField(default=0, srid=4326),
            preserve_default=False,
        ),
    ]

Answer 1

您在初始 Territorio 模型创建后添加 geometry 字段，但您没有向该字段提供 default 值。
为了应用此迁移，Django 要求您（在 ./manage.py makemigrations 部分之后的终端中）为 table 中的任何现有记录手动提供 default 值。您一定已经回答了 0 那个问题，因此问题出现了（您实质上是在 Geometry 字段中添加了一个 Integer 值）。

由于您允许 null=True 进入 geometry 字段，因此简单的解决方法是：

Revert the migrations to the previous one (0007_auto_20200406_1506):
```
./manage.py migrate my_app 0007_auto_20200406_1506
```
删除迁移文件0008_territorio_geometry.py.
检查数据库中的 table django_migrations 条目 0008_territorio_geometry 并将其删除（如果存在）。

为 geometry 字段提供默认值 None，如下所示：

geometry = models.GeometryField(spatial_index=True, null=True, default=None)

根据您的喜好重新创建迁移，然后应用它：

./manage.py makemigrations --name 0008_territorio_geometry
./manage.py migrate

你应该准备好了:)

Answer 2

`

dependencies = [
    ('map', '0007_auto_20200406_1506'),
]

operations = [
    migrations.AddField(
        model_name='territorio',
        name='geometry',
        field=django.contrib.gis.db.models.fields.GeometryField(default=0, srid=4326),
        preserve_default=False,
    ),
]`

变化

`

dependencies = [
    ('map', '0007_auto_20200406_1506'),
]

operations = [
    migrations.AddField(
        model_name='territorio',
        name='geometry',
        field=django.contrib.gis.db.models.fields.GeometryField(default=0, srid=4326),
        preserve_default=None,
    ),
]`

GeoDjango migrate giving the following error - ValueError: Cannot use object with type int for a spatial lookup parameter

GeoDjango migrate giving the following error - ValueError: Cannot use object with type int for a spatial lookup parameter

python

django

django-models

geodjango