mongodb - 使用 mongodb 中的搜索条件更新最后一行

Question

下面是我的收藏:

db.himtest.find({name:"himanshu"})
{ "_id" : ObjectId("56f1667611c54cf649076577"), "name" : "himanshu", "age" : 45,
 "points" : 10 }
  { "_id" : ObjectId("56f1667c11c54cf649076578"), "name" : "himanshu", "age"   : 35,
"points" : 10 }
{ "_id" : ObjectId("56f1669511c54cf64907657b"), "name" : "himanshu", "age" : 35,
 "points" : 1100 }
 { "_id" : ObjectId("56f1669a11c54cf64907657c"), "name" : "himanshu", "age" : 35,
 "points" : 11000 }
 { "_id" : ObjectId("56f1669d11c54cf64907657d"), "name" : "himanshu", "age" : 45,
  "points" : 11000 }
 { "_id" : ObjectId("56f166a311c54cf64907657e"), "name" : "himanshu", "age" : 45,
     "points" : 1200 }

现在我想根据任何选择标准更新最后一行，例如:

    db.himtest.find({name:"himanshu",age:45}).sort({_id:-1}).limit(1).update({points:100});

Answer 1

您可以使用 findAndModify 执行此操作它允许您包含一个排序规范来标识要更新的匹配文档:

db.himtest.findAndModify({
  query: {name: "himanshu", age: 45},
  sort: {_id: -1},
  update: {$set: {points: 100}},
  new: true
})

如果您使用的是 v3.2 或更高版本，您还可以使用 findOneAndUpdate :

db.himtest.findOneAndUpdate(
    {name: "himanshu", age: 45},
    {$set: {points: 100}},
    {
        sort: {_id: -1},
        returnNewDocument: true
    })