Django - UNIQUE约束在外键上失败

19 浏览
0 Comments

Django - UNIQUE约束在外键上失败

我在我的Django数据库（SQLite）上有两个表，Field_Of_Research和Conference。Conference有三个外键与Field_Of_Research的主键关联。在迁移命令期间，我通过读取csv文件来填充数据库，但是当插入具有相同外键值（对于所有三个键）的两个conference时，会显示UNIQUE constraint failed错误。如果我使用管理员页面插入会议，数据库会出现相同的错误。我该如何解决这个问题？\nmodel.py\n

class Field_Of_Research(models.Model):
     for_id = models.PositiveIntegerField(primary_key=True)
     name = models.CharField(max_length=256)
def __str__(self):
    return self.name
class Conference(models.Model):
    conf_id = models.PositiveIntegerField(primary_key=True)
    title = models.CharField(max_length=256)
    primary_for = models.ForeignKey(to=Field_Of_Research, default=0, on_delete=models.SET_DEFAULT, related_name='primary_for')
    secondary_for = models.ForeignKey(to=Field_Of_Research, default=0, on_delete=models.SET_DEFAULT, related_name='secondary_for')
    third_for = models.ForeignKey(to=Field_Of_Research, default=0, on_delete=models.SET_DEFAULT, related_name='third_for')
def __str__(self):
    return self.title

\npopulate.py\n

with open('./server/api/database/files/fields_of_research.csv') as csv_file:
    csv_reader = csv.reader(csv_file, delimiter=';')
    for row in csv_reader:
        f = Field_Of_Research.objects.get_or_create(
            for_id=row[0],
            name=row[1]
        )
    print('Fields of Research done.')
#填充conferences数据库
with open('./server/api/database/files/conferences.csv') as csv_file:
    csv_reader = csv.reader(csv_file, delimiter=';')
    for row in csv_reader:
        print(row)
        c = Conference.objects.get_or_create(
            conf_id=row[0],
            title=row[1],
            primary_for=Field_Of_Research.objects.get(for_id=int(row[3])),
            secondary_for=Field_Of_Research.objects.get(for_id=int(row[4])),
            third_for=Field_Of_Research.objects.get(for_id=int(row[5])),
        )
    print('Conferences done.')

\n错误信息\n

  File "C:\Users\andre\AppData\Local\Programs\Python\Python38-32\lib\site-packages\django\db\backends\utils.py", line 86, in _execute
return self.cursor.execute(sql, params)
  File "C:\Users\andre\AppData\Local\Programs\Python\Python38-32\lib\site-packages\django\db\backends\sqlite3\base.py", line 396, in execute
return Database.Cursor.execute(self, query, params)
  sqlite3.IntegrityError: UNIQUE constraint failed: api_conference.third_for_id

0