Question

I use mongo, and I have a little problem here. I want to get a record, but I just have the id of an array list inside record. This is what my data looks like.

{    
   "_id": ObjectId("1113000001"),    
   "menu": "desertsunday",   
  "fruit": {
      "0": ObjectId("102b000000"),
      "1": ObjectId("5200000000"),
      "2": ObjectId("2900000000"),
      "3": ObjectId("9870000002")   } 
 }

I just have 102b000000 for get the record, I need to get the menu from there but I can’t get it with standard mongo. Can anybody help me ?

Answer 1

Actually fruit in you schema is not array, it is list of objects, because of this there is only one way to get root document by one fruit id:

db.items.find({"fruit.0": ObjectId("102b000000")}) 

In above query you should know ordinal number of fruit to fetch root document.

But if you can redesign your database as follows:

{    
   "_id": ObjectId("1113000001"),    
   "menu": "desertsunday",   
   "fruit": [
      { i:0, id: ObjectId("102b000000") },
      { i:1, id: ObjectId("5200000000") }
    ]
}

you can easy fetch root doc by embedded array item id:

db.items.find({"fruit.id": ObjectId("102b000000")})