如何在猫鼬中更新多个文档?

问题描述

我找到了以下脚本:

Device.find(function(err, devices) {
  devices.forEach(function(device) {
    device.cid = '';
    device.save();
  });
});

MongoDB 具有多"功能.多个文档的更新标志，但我无法使用猫鼬进行此操作.这还不支持还是我做错了什么?

MongoDB has the "multi" flag for an update over multiple documents but I wasn't able to get this working with mongoose. Is this not yet supported or am I doing something wrong?

Device.update({}, {cid: ''}, false, true, function (err) {
  //...
});

推荐答案

目前我认为 Mongoose 中的 update() 存在一些问题，参见:https://groups.google.com/forum/#%21topic/mongoose-orm/G8i9S7E8Erg和 https://groups.google.com/d/topic/mongoose-orm/K5pSHT4hJ_A/讨论.

Currently I believe that update() in Mongoose has some problems, see:https://groups.google.com/forum/#%21topic/mongoose-orm/G8i9S7E8Ergand https://groups.google.com/d/topic/mongoose-orm/K5pSHT4hJ_A/discussion.

但是，请检查文档以获取更新:http://mongoosejs.com/docs/api.html(在模型下).定义是:

However, check the docs for update: http://mongoosejs.com/docs/api.html (its under Model). The definition is:

早期解决方案(猫鼬 5+ 版本后折旧)

Model.update = function (query, doc, options, callback) { ... }

您需要在对象内传递选项，因此您的代码将是:

You need to pass the options inside an object, so your code would be:

Model.update = function ({}, {cid: ''}, {multi: true}, function(err) { ... });

新解决方案

Model.updateMany = function (query, doc, callback) { ... }

Model.updateMany = function ({}, {cid: ''}, function(err) { ... });

我相信 Mongoose 将您的 cid 包装在 $set 中，因此这与在 mongo shell 中运行相同的更新不同.如果您在 shell 中运行它，那么所有文档都将被替换为一个带有单个 cid: '' 的文档.

I believe that Mongoose wraps your cid in a $set, so this is not the same as running that same update in the mongo shell. If you ran that in the shell then all documents would be replaced by one with a single cid: ''.

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