Querying a documents with nested array in mongoDB

Question

EDIT: Below query were executed from DataGrip, mongodb version 4.2.6

I am fairly new to mongoDB and I am digging through a lot of documents but couldn't figure out how this would work.

My collections is like this:

db.cards.insertMany([
{
  "Name": "SingleFaced Card",
  "Face": [
    {"Type": "Front", "Color": ["Black"]},
  ]
},
{
  "Name": "DoubleFaced Card",
  "Face": [
    {"Type": "Front", "Color": ["Black"]},
    {"Type": "Back", "Color": ["Red", "Yellow"]}
  ]
},
]);

I would like to query the card, that has at least one face with the given color, say Red.

I have tried lots of different options, all of them give me a count of 0.

db.cards.count({"Face.Color": "Red"}); // 0 record
db.cards.count({"Face.Color": ["Red"]}) // 0 record
db.cards.count({"Face.Color": {$elemMatch:{$in:['Red']}}}) // 0 record
db.cards.count({"Face.Color": {$elemMatch:{$all:['Red']}}}) // 0 record
db.cards.count({"Face.Color": {$elemMatch:{$elemMatch:{$in:['Red']}}}}); // 0 record

I initially thought there is something wrong with my installation, but the below queries on nested fields worked.

db.cards.count({"Face.Type" : "Front"}); // 2 record
db.cards.count({"Face.Type" : "Back"}); // 1 record

Any suggestions on how should I make this work? Am I using the wrong design choice here?

thammada.ts · Accepted Answer · 2020-04-29 20:52:34Z

2

Your third query already works

db.cards.count({ "Face.Color": { $elemMatch: { $in: ['Red'] } } })

answered Apr 29, 2020 at 20:52

thammada.ts

5,2653 gold badges26 silver badges35 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

lanrete Over a year ago

Thanks for the link! I did some comparison on the environment. I was running the examples through DataGrip from JetBrain on mongodb 4.2.6. I have downgraded the db version to 4.2.5 and re-run the query from python package pymongo and it works now. Perhaps there is a bug on either DataGrip or version 4.2.6

Collectives™ on Stack Overflow

Querying a documents with nested array in mongoDB

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related