MongoDB：如何在集合中添加`id`字段？

Question

我想在集合中添加id字段，该数字从1开始。 例如， 有一个收藏文章：

{"_id" : ObjectId("98r498jfgragaja9ra4"),"titile":"foo","content":"foo..."}
{"_id" : ObjectId("498aut89auhgua4940q"),"titile":"bar","content":"bar..."}
{"_id" : ObjectId("30ua9ah984yhtauiga9"),"titile":"hello","content":"hello..."}

添加id字段后，结果如下所示：

{"_id" : ObjectId("98r498jfgragaja9ra4"),"titile":"foo","content":"foo...","id":"1"}
{"_id" : ObjectId("498aut89auhgua4940q"),"titile":"bar","content":"bar...","id":"2"}
{"_id" : ObjectId("30ua9ah984yhtauiga9"),"titile":"hello","content":"hello...","id":"3"}

怎么做？

Answer 1

MongoDB的文档提供了一些有关如何执行此操作的建议：

https://docs.mongodb.com/v3.0/tutorial/create-an-auto-incrementing-field/