MongoDB查询以更新所有匹配特定ID的文档
updateMany()方法更新所有符合过滤条件的文档。让我们创建一个包含文档的集合-> db.demo476.insertOne({_id:1,"Name":"Chris"});
{ "acknowledged" : true, "insertedId" : 1 }
> db.demo476.insertOne({_id:2,"Name":"David"});
{ "acknowledged" : true, "insertedId" : 2 }
> db.demo476.insertOne({_id:3,"Name":"Bob"});
{ "acknowledged" : true, "insertedId" : 3 }
> db.demo476.insertOne({_id:4,"Name":"Carol"});
{ "acknowledged" : true, "insertedId" : 4 }在find()方法的帮助下显示集合中的所有文档-
> db.demo476.find();
这将产生以下输出-
{ "_id" : 1, "Name" : "Chris" }
{ "_id" : 2, "Name" : "David" }
{ "_id" : 3, "Name" : "Bob" }
{ "_id" : 4, "Name" : "Carol" }以下是查询以更新所有匹配特定ID的文档-
> db.demo476.updateMany({_id:{$in:[1,3]}},{$set:{Name:"Robert"}});
{ "acknowledged" : true, "matchedCount" : 2, "modifiedCount" : 2 }在find()方法的帮助下显示集合中的所有文档-
> db.demo476.find();
这将产生以下输出-
{ "_id" : 1, "Name" : "Robert" }
{ "_id" : 2, "Name" : "David" }
{ "_id" : 3, "Name" : "Robert" }
{ "_id" : 4, "Name" : "Carol" }