我们希望一次检索所有表记录，以实现如何在Django orm中实现类似SQL查询的功能。
示例SQL查询：
select *
from Company_info
inner join Bank_info on Bank_info.manufacturer = Company_info.manufacturer
inner join Company_info on Company_info.manufacturer = Company_info.manufacturer
inner join Transport_info on Transport_info.manufacturer = Company_info.manufacturer
码：
class Manufacturer(models.Model):
name = models.CharField(max_length=42)
class Bank_info(models.Model):
account = models.CharField(max_length=42)
manufacturer = models.ForeignKey(Manufacturer, on_delete= models.CASCADE)
class Company_info(models.Model):
name= models.CharField(max_length=42)
manufacturer = models.ForeignKey(Manufacturer, on_delete= models.CASCADE)
class Transport_info(models.Model):
name= models.CharField(max_length=42)
manufacturer = models.ForeignKey(Manufacturer, on_delete= models.CASCADE)
您可以为此使用prefetch_related，如注释中所述：
Manufacturer.objects.all().prefetch_related('related_name2', 'related_name3', 'related_name4')
实际上，这不会执行SQL INNER JOIN，但会在Python级别上连接预取的对象-使用相关对象字段时，这将减少对数据库的命中率。
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