通过Node.js将文档插入MongoDB时出错 [英] Error when inserting a document into MongoDB via Node.js
问题描述
我正在尝试在Node.js中将文档插入MongoDB。我已成功读取数据库,并通过命令行界面添加了文档。但是,我无法从JavaScript插入文档。如果我这样做,我收到一个错误:
I'm trying to insert a document into MongoDB in Node.js. I have read from the DB successfully, and added documents via the command-line interface. However, I can't insert a document from JavaScript. If I do, I get an error:
错误:没有提供的回调就不能使用writeConcern
Error: Cannot use a writeConcern without a provided callback
这是我的代码:
var mongodb = require("mongodb");
var MongoClient = mongodb.MongoClient;
MongoClient.connect("mongodb://localhost:27017/test", function(err, db) {
if (!err) {
db.collection("test").insert({ str: "foobar" });
}
});
我不能为我的生活弄清楚为什么我会收到这个错误。
I can't for the life of me figure out why I get this error.
我做错了什么,我应该怎么做?
What did I do wrong, and how should I do this instead?
推荐答案
您需要为插入
调用提供回调函数,以便该方法可以将插入过程中发生的任何错误传达给您。
You need to provide a callback function to your insert
call so that the method can communicate any errors that occur during the insert back to you.
db.collection("test").insert({ str: "foobar" }, function (err, inserted) {
// check err...
});
或者,如果您真的不在乎插入是否成功,则通过写入关注options参数中的值为0:
Or, if you truly don't care whether the insert succeeds or not, pass a write-concern value of 0 in the options parameter:
db.collection("test").insert({ str: "foobar" }, { w: 0 });
这篇关于通过Node.js将文档插入MongoDB时出错的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!