Python：尝试在终端中运行脚本但出现错误 IntegrityError：NOT NULL 约束失败

Question

所以我试图从命令行运行一个脚本来解析本地存储的 xml 文件中的信息。 每当我运行脚本时，我都会收到此错误。

Traceback (most recent call last):
  File "updatedb.py", line 54, in <module>
    populate()
  File "updatedb.py", line 37, in populate
    diameter=diameter, streetNumber=streetNumber, street=street)
  File "updatedb.py", line 41, in add_tree
    tree = Tree.objects.get_or_create(treeId=treeId)[0]
  File "/usr/lib/python2.7/site-packages/django/db/models/manager.py", line 92, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/usr/lib/python2.7/site-packages/django/db/models/query.py", line 424, in get_or_create
    return self._create_object_from_params(lookup, params)
  File "/usr/lib/python2.7/site-packages/django/db/models/query.py", line 465, in _create_object_from_params
    six.reraise(*exc_info)
  File "/usr/lib/python2.7/site-packages/django/db/models/query.py", line 457, in _create_object_from_params
    obj.save(force_insert=True, using=self.db)
  File "/cygdrive/c/users/user/workspace/hug/timetravellingtrout/hug_project/hug/models.py", line 30, in save
    super(Tree, self).save(*args, **kwargs)
  File "/usr/lib/python2.7/site-packages/django/db/models/base.py", line 589, in save
    force_update=force_update, update_fields=update_fields)
  File "/usr/lib/python2.7/site-packages/django/db/models/base.py", line 617, in save_base
    updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)
  File "/usr/lib/python2.7/site-packages/django/db/models/base.py", line 698, in _save_table
    result = self._do_insert(cls._base_manager, using, fields, update_pk, raw)
  File "/usr/lib/python2.7/site-packages/django/db/models/base.py", line 731, in _do_insert
    using=using, raw=raw)
  File "/usr/lib/python2.7/site-packages/django/db/models/manager.py", line 92, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/usr/lib/python2.7/site-packages/django/db/models/query.py", line 921, in _insert
    return query.get_compiler(using=using).execute_sql(return_id)
  File "/usr/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 921, in execute_sql
    cursor.execute(sql, params)
  File "/usr/lib/python2.7/site-packages/django/db/backends/utils.py", line 81, in execute
    return super(CursorDebugWrapper, self).execute(sql, params)
  File "/usr/lib/python2.7/site-packages/django/db/backends/utils.py", line 65, in execute
    return self.cursor.execute(sql, params)
  File "/usr/lib/python2.7/site-packages/django/db/utils.py", line 94, in __exit__
    six.reraise(dj_exc_type, dj_exc_value, traceback)
  File "/usr/lib/python2.7/site-packages/django/db/backends/utils.py", line 65, in execute
    return self.cursor.execute(sql, params)
  File "/usr/lib/python2.7/site-packages/django/db/backends/sqlite3/base.py", line 485, in execute
    return Database.Cursor.execute(self, query, params)
django.db.utils.IntegrityError: NOT NULL constraint failed: hug_tree.streetNumber

我不知道是什么导致了它，我已经尝试了我找到的有关此错误的所有可能的解决方案。 我试过使用null=True ， blank=True ，迁移这些东西，但没有任何效果。

我的其他文件如下所示： models.py

class Tree(models.Model):

    treeId = models.IntegerField(primary_key=True)
    neighbourhood = models.CharField(max_length=128)
    commonName = models.CharField(max_length=128)
    diameter = models.FloatField(null=True, blank=True)
    streetNumber = models.PositiveSmallIntegerField()
    street = models.CharField(max_length=128)

    def save(self, *args, **kwargs):
                self.slug = slugify(self.treeId)
                super(Tree, self).save(*args, **kwargs)

    def __unicode__(self):
        return str(self.treeId)

脚本

def populate():
    parsedfiles = minidom.parse('C:\Users\User\Downloads\New folder\StreetTrees_ArbutusRidge.xml')
    treelist = parsedfiles.getElementsByTagName('StreetTree')
    for alltrees in treelist:
        treeId = alltrees.getAttribute('TreeID')
        neighbourhood = alltrees.getElementsByTagName('NeighbourhoodName')
        commonName = alltrees.getElementsByTagName('CommonName')
        diameter = alltrees.getElementsByTagName('Diameter')
        streetNumber = alltrees.getElementsByTagName('CivicNumber')
        street = alltrees.getElementsByTagName('StdStreet')
        add_tree(treeId=treeId, neighbourhood=neighbourhood, commonName=commonName,
                 diameter=diameter, streetNumber=streetNumber, street=street)




def add_tree(treeId, neighbourhood, commonName, diameter, streetNumber, street):
    tree = Tree.objects.get_or_create(treeId=treeId)[0]
    tree.neighbourhood = neighbourhood
    tree.commonName = commonName
    tree.diameter = diameter
    tree.streetNumber = streetNumber
    tree.street = street
    tree.save()
    return tree


# Start execution here!
if __name__ == '__main__':
    print "Starting update script..."
    populate()

Answer 1

getElementsByTagName()返回元素列表。 您的字段只接​​受一个正小整数（不是列表）。 您应该更改以下行以定位单个元素：

streetNumber = alltrees.getElementsByTagName('CivicNumber')[0]

您可能也必须为其他领域执行此操作...