Finding document in mongodb collection where key matches particular value in list of documents

Question

I'm new to MongoDB and I'm trying to query the following collection (named sample):

{
    "_id": "thresholds",
    "thresholds": [{
        "GRADE": "CC004",
        "C": "",
        "CF": "",
        "MN": "0.01",
        "N": "",
        "P": "0.03",
        "SI": "",
        "CR": ""
    }, {
        "GRADE": "CC005",
        "C": "",
        "CF": "",
        "MN": "",
        "N": "",
        "P": "",
        "SI": "",
        "CR": ""
    }]
}

I'm trying to retrieve the entire record where the "GRADE" is "CC004".

Right now, I'm doing the following: db.sample.find({"thresholds": {"GRADE": "CC004"}}). However, it's returning null value because nothing was found. How can I rephrase my query to find my entry of interest?

In that case, have you tried the using "distinct" instead of "find"? For example: db.sample.distinct("thresholds", {'GRADE': 'CC005'}) — Moe, Jun 04 '20 at 00:41
Does this answer your question? [Retrieve only the queried element in an object array in MongoDB collection](https://stackoverflow.com/questions/3985214/retrieve-only-the-queried-element-in-an-object-array-in-mongodb-collection) — whoami - fakeFaceTrueSoul, Jun 04 '20 at 03:36

Nelson Hernández · Answer 1 · 2020-06-04T01:16:40.830

0

You could make the following query:

db.sample.find({"thresholds.GRADE": "CC004"})

edited Jun 04 '20 at 01:16

answered Jun 04 '20 at 00:21

Nelson Hernández

1
3

Hi @Neslon, thanks for your reply. I tried this and it retrieved the ALL the documents in the list not that particular one I'm interested in. – kryogenic1 Jun 04 '20 at 00:23
Please only post answers in English. Thanks. – David Buck Jun 04 '20 at 00:33

Finding document in mongodb collection where key matches particular value in list of documents

1 Answers1