MongoDB/Mongoose query based on multiple subdocuments

Question

I'm brand new to MongoDB and Mongoose. I'm currently building an app that has a client collection that contains an array of accounts that the client has.

I'd like to query the collection based on specifics of the accounts the client has. For example, I need to return the client that is:

• clientType: "Standard"
• Has two accounts:
  • accountType: "FML", balance: $gt 3000
  • accountType: "OMG", balance: $lt 3000

Below is a sample document:

{
    clientDetails: {
        cardNumber: "0123456",
        firstName: "Bob",
        lastName: "Dole",
        clientType: "Standard"
    },
    accounts: [
        {
            accountNumber: "123",
            accountType: "FML",
            balance: 4000.00
        },
        {
            accountNumber: "234",
            accountType: "OMG",
            balance: 2000
        }
    ]
}

So far, I've only figured out how to build a query that can get a client of clientType "Standard" with accountTypes ["FML","OMG] but I can't figure out how to specify the balance condition for the specific accountTypes.

ClientModel
    .find({
        "clientDetails.clientType": "Standard",
        "accounts.accountType": { $all ["FML", "OMG"]
    })
    .then(
        function(){ //etc..},
        function(err){ //etc...}
    );

Answer 1

You can use $all with $elemMatch .

ClientModel
    .find({
        "clientDetails.clientType": "Standard",
        "accounts": 
          { 
             $all: [
                     { "$elemMatch" : { accountType: "FML", balance: { $gt: 3000} } },
                     { "$elemMatch" : { accountType: "OMG", balance: { $lt: 3000} } } 
               ]
          }
    })
    .then(
        function(){ //etc..},
        function(err){ //etc...}
    );