Mongodb Embedded Document Finding and Modifying Problems

  mongodb, question

The format of the data is as follows:

{
 "_id" : 1,
 "people_id" : 1,
 "albums" : [
 {
 "id" : 1,
 "name" : "123",
 "privilege" : 0,
 },
 {
 "id" : 2,
 "name" : "Q",
 "privilege" : 5,
 },
 {
 "id" : 3,
 "name" : "Q",
 "privilege" : 5,
 },
 ]
 }
 
 {
 "_id" : 2,
 "people_id" : 2,
 "albums" : [
 {
 "id" : 1,
 "name" : "4",
 "privilege" : 0,
 },
 {
 "id" : 2,
 "name" : "5",
 "privilege" : 0,
 }
 ]
 }

What I am thinking now is
1 ,How to write mongodb’s query command when querying embedded documents with people_id 1 and privilege 5

2,The name field value of the embedded document with update people_id 2 and permission id 2 is 6. How is the update command written?

Query me
db.find({“people_id” : 1,”albums”:{“$elemMatch” : {“privilege” : 5}}})
To try to match, but match out:

{
 "_id" : 1,
 "people_id" : 1,
 "albums" : [
 {
 "id" : 1,
 "name" : "123",
 "privilege" : 0,
 },
 {
 "id" : 2,
 "name" : "Q",
 "privilege" : 5,
 },
 {
 "id" : 3,
 "name" : "Q",
 "privilege" : 5,
 },
 ]
 }

I don’t want the one with id 1, but only the one with id 2 and ID 3.

Revision, I really won’t,
Please also help us to propose solutions, thank you very much!

The query statement can be simplified as follows:

db.demo.find({"people_id" : 1, "albums.privilege": 5})

The query results return documents that meet the matching criteria. Although the returned fields can be mapped, it is true that you cannot only return what you said.Id is 2 and 3.The document of. But now that you have a json document that meets the criteria, you can write a program to get the desired embedded subdocuments.

The update statement is as follows:

db.demo.update({people_id:2, "albums.id":2}, { $set : {"albums.$.name":6 }})

However, only the first matching subdocument in the array is updated, howeveralbums.idIt seems that it is the only one and should be able to meet your needs.

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