{$ unset：{field：1}}中1的含义是什么(What does 1 mean in { $unset : { field : 1} })

 在下面的代码片段中，我能够从具有不同参数的集合中删除两个关键字段（即One为1，另一个为0）。 
 
> i = { name : 'name', age : 25, gender : 'female' };
{ "name" : "name", "age" : 25, "gender" : "female" }
> db.users.insert(i)
> db.users.find()
{ "_id" : ObjectId("4e8b5b5e654f46ccc304e44e"), 
  "name" : "name", "age" : 25, "gender" : "female" }
> db.users.update({ name : 'name'}, 
                  {$unset : {age : 1, gender : 0}}) // check here
> db.users.find()
{ "_id" : ObjectId("4e8b5b5e654f46ccc304e44e"), "name" : "name" }
> 
 
 参考：MongoDB $ unset 
 
 问题>以下手册中1的用法是什么？ 
 
 
 
 {$ unset：{field：1}} 
 

In the following snippet, I am able to remove two key fields from a collection with different parameters (i.e. One is 1 and the other is 0).
 
> i = { name : 'name', age : 25, gender : 'female' };
{ "name" : "name", "age" : 25, "gender" : "female" }
> db.users.insert(i)
> db.users.find()
{ "_id" : ObjectId("4e8b5b5e654f46ccc304e44e"), 
  "name" : "name", "age" : 25, "gender" : "female" }
> db.users.update({ name : 'name'}, 
                  {$unset : {age : 1, gender : 0}}) // check here
> db.users.find()
{ "_id" : ObjectId("4e8b5b5e654f46ccc304e44e"), "name" : "name" }
> 
 
Reference: MongoDB $unset
 
Question> What is the usage of 1 in the following manual?
 
 
 
{ $unset : { field : 1} }
 

原文：https://stackoverflow.com/questions/7652990