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