wuming
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是否可以在 Django 中使用一句话实现对数据库中的某个字段的值加 1

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  •   wuming · Aug 5, 2014 · 8664 views
    This topic created in 4364 days ago, the information mentioned may be changed or developed.
    我现在的做法是先用Django读出这个字段的值,加一后再更新到数据库中。有没有其他更便捷的方法实现?

    现在的代码类似这样:
    some_object = SomeObject.objects.get(id=some_id)
    some_value = some_object.some_value
    some_value += 1
    SomeObject.objects.filter(id=some_id).update(some_value=some_value)
    4 replies    2014-08-06 00:27:45 +08:00
    xiwangzishi
        1
    xiwangzishi  
       Aug 5, 2014   ❤️ 1
    可以
    ```
    RootCount.objects.filter(key = n.key).update(success = F('success') + 1,value = value_str,support = True)
    ```
    wenbinwu
        2
    wenbinwu  
       Aug 5, 2014
    search 'Filters can reference fields on the model' in django document
    wuming
        3
    wuming  
    OP
       Aug 5, 2014
    @xiwangzishi 感谢,已解决
    20150517
        4
    20150517  
       Aug 6, 2014
    关键楼主例子,不是不快捷,是根本不线程安全啊.......
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