NoSQL学习之路 (五)：更新操作符(Update Operators).2nd-Mysql Tutorial-php.cn

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NoSQL学习之路 (五)：更新操作符(Update Operators).2nd

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Jun 07, 2016 pm 05:45 PM

nosqloperaupdatestudyoperaterenew

本文地址: 欢迎转载，请保留此链接！通常文档只会有一部分要更新。利用原子的更新修改器，可以使得这种部分更新极为髙效。更新修改器是种特殊的键，用来指定复杂的更新操作，比如调整、增加或者删除键，还可能是操作数组或者内嵌文档。字段更新操作符 Fi

　　本文地址: 欢迎转载，请保留此链接• •！　　

　　通常文档只会有一部分要更新。利用原子的更新修改器，可以使得这种部分更新极为髙效。更新修改器是种特殊的键，用来指定复杂的更新操作，服务器空间，比如调整、增加或者删除键，还可能是操作数组或者内嵌文档。

字段更新操作符 Field Update Operators 　　$set

　　"$set"用来指定一个键的值。如果这个键不存在，则创建它。

　　我们往下面的一条用户资料添加“兴趣”信息，

db.users.insert({"name":"egger", "age": 28, "sex" : "male"}) ，香港虚拟主机，服务器空间

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