在数据库中查找特定字段的重复条目 [英] Find duplicate entries in database for specific fields
问题描述
我有一个模型，其中包含姓名，学校，电子邮件，地址等字段.
I have model having fields as name, school, email, address etc.
我想找出在 name 和 school 字段中具有相同条目的行?
I want to find out the rows for which there is same entry for name and school field ?
eg:
name school email
abc mps abc@gmail.com
abc mps abc@gmail.com
xyz vps xyz@gmail.com
abc mps abc@gmail.com
poi vps poi@gmail.com
jkl vps jkl@gmail.com
像 name abc和 school mps一样，mps是3个条目，而xyz和vps有2个条目我可以嵌套 for 循环和迭代方式，以对照表中的所有行检查名称和学校字段.那将是性能下降(n * n)
like for name abc and school mps ther are 3 entries and for xyz and vps there are 2 entries
I can nested for loop and iterative manner to check the name and school fields against all the rows in the table. That would be performance hit (n*n)
还有其他方法可以找到吗?
Is there any other way to find out ?
推荐答案
distinct() will serve the purpose. The following will solve your problem
model_name.objects.values_list('name').distinct()
如果您想要字典，则必须这样做
If you want dictionary then you have to do this
model_name.objects.values('name').distinct()
希望能解决您的问题！
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