使用MongoDB对ID进行排序并反转项目
$natural以自然顺序返回文档。要反转项目，请使用$natural：-1。让我们创建一个包含文档的集合：
> db.demo710.insertOne({id:101,Name:"Robert"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5ea83a855d33e20ed1097b7a")
}
> db.demo710.insertOne({id:102,Name:"Carol"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5ea83a8d5d33e20ed1097b7b")
}
> db.demo710.insertOne({id:103,Name:"Mike"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5ea83a935d33e20ed1097b7c")
}
> db.demo710.insertOne({id:104,Name:"Sam"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5ea83a9b5d33e20ed1097b7d")
}在find()方法的帮助下显示集合中的所有文档-
> db.demo710.find();
这将产生以下输出-
{ "_id" : ObjectId("5ea83a855d33e20ed1097b7a"), "id" : 101, "Name" : "Robert" }
{ "_id" : ObjectId("5ea83a8d5d33e20ed1097b7b"), "id" : 102, "Name" : "Carol" }
{ "_id" : ObjectId("5ea83a935d33e20ed1097b7c"), "id" : 103, "Name" : "Mike" }
{ "_id" : ObjectId("5ea83a9b5d33e20ed1097b7d"), "id" : 104, "Name" : "Sam" }以下是对项目进行排序和反转的查询-
> db.demo710.find().sort({$natural:-1});这将产生以下输出-
{ "_id" : ObjectId("5ea83a9b5d33e20ed1097b7d"), "id" : 104, "Name" : "Sam" }
{ "_id" : ObjectId("5ea83a935d33e20ed1097b7c"), "id" : 103, "Name" : "Mike" }
{ "_id" : ObjectId("5ea83a8d5d33e20ed1097b7b"), "id" : 102, "Name" : "Carol" }
{ "_id" : ObjectId("5ea83a855d33e20ed1097b7a"), "id" : 101, "Name" : "Robert" }