mongo db find操作查询不起作用

Question

Am new to mongodb

db.myjobs.find() gets following results

{ "_id" : ObjectId("52849a7b8dd61980d1b49b87"), "browser" : "FF20", "id" : "70", "jobs" : [ { "_id" : "5281d1680d0f2f2aaec5787e",   "date" : "Tue Nov 12 2013 12:27:44 GMT+0530 (IST)", "id" : "29" } ],  "os" : "VM-WIN7-64", "server" : "172.16.2.120" }

from the above result i have to return "os" : "VM-WIN7-64" on the basis of id=29 inside jobs

am using following code and it is not correct.

db.myjobs.find( { id: 29 } )

How can i get "os" : "VM-WIN7-64" by inputting id (id=29) inside jobs no need to get os details using "id":"70"

Answer 1

Like this:

db.myjobs.find( { "jobs.id": "29" } )

MongoDB doesn't perform recursive searches so if want to find field in nested document you have to provide a path to the field using dot notation.

Moreover fields in MongoDB are typed so string "29" is not equal to number 29

Answer 2

You can use dot operator to go inside of the object.

db.myjobs.find({
   "jobs.id": "29"
})

Answer 3

The following should work

db.myjobs.find({"jobs.id":"29"},{"_id":0,"os":1})