Mongodb 多更新，只更新mongo-shell中的单个文档

Question

我正在学习 mongodb 并尝试使用 {$multi: true} 选项执行简单的多文档更新，但它只更新单个文档。

> db.users.update({'color': 'black'}, {$set: {'title': 'blackers'}}, {$multi: true});

WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })

> db.users.find({'color': 'black'});

{ "_id" : ObjectId("5562312f061fa19e6cebc7e4"), "color" : "black", "hobby" : [ "dancing", "breaking", "drawing", "praying", "smiling" ], "name" : "john", "schools" : [ "mlimwa", "martin", "ignatus", "eget", "jubilee", "canon" ], "title" : "blackers" }

{ "_id" : ObjectId("5564057bb0f557f0c0589e66"), "color" : [ "black" ], "name" : "demo" }

{ "_id" : ObjectId("556424fc1dd78ab02dd2918f"), "color" : "black", "name" : "tola" }

>db.version()
3.0.3

请帮助我真的卡住了..

Answer 1

不是$multi，只写{multi:true}

db.users.update({'color': 'black'}, {$set: {'title': 'blackers'}}, {multi: true});

请参阅此处的文档，以获得有关 upsert 或 writeconcern 参数的进一步帮助 http://docs.mongodb.org/manual/reference/method/db.collection.update/