【Django 2021年最新版教程17】数据库操作 models 存在更新不存在新建update_or_create

快来打我* 2022-10-05 08:57 57阅读 0赞

# 一、存在则更新 不存在则新建 update\_or\_create方法 #

Model.objects.update_or_create(defaults,**kwargs)

*  defaults是用来更新的
 *   kwargs是用来查询的

defaults是需要更新的数据字典，后面参数是用来查询的是否存在的，如果存在就更新，反之insert  
例如：

defaults = dict()
    defaults['name'] = 'Jeff'
    defaults['idcard'] = '123456'
    defaults['content'] = 'hello world'
    
    User.objects.update_or_create(defaults=defaults, name='Jeff', idcard='123456')

返回值为元组: (object, created)，

*  object为新建或者更新的对象，
 *  created为一个布尔值，表示是新建还是更新，True为新建，False为更新

![20210608153358513.png][]

# 二、不存在就创建get\_or\_create方法 #

User.objects.get_or_create(username = 'kkk', password = 'ppp')

参考

[https://segmentfault.com/q/1010000010168141][https_segmentfault.com_q_1010000010168141]

[https://blog.csdn.net/qq\_35968173/article/details/107639786][https_blog.csdn.net_qq_35968173_article_details_107639786]

[https://www.cnblogs.com/xshan/p/12765610.html][https_www.cnblogs.com_xshan_p_12765610.html]

[https://www.cnblogs.com/iiiiiher/p/11646309.html][https_www.cnblogs.com_iiiiiher_p_11646309.html]

[20210608153358513.png]: /images/20221005/eb9a4853bad84e29b81d98e1fe1aa43b.png
[https_segmentfault.com_q_1010000010168141]: https://segmentfault.com/q/1010000010168141
[https_blog.csdn.net_qq_35968173_article_details_107639786]: https://blog.csdn.net/qq_35968173/article/details/107639786
[https_www.cnblogs.com_xshan_p_12765610.html]: https://www.cnblogs.com/xshan/p/12765610.html
[https_www.cnblogs.com_iiiiiher_p_11646309.html]: https://www.cnblogs.com/iiiiiher/p/11646309.html