Find value in a MongoDB Array with multiple criteria?

To find values in a MongoDB array with multiple criteria, use the $elemMatch operator combined with comparison operators like $gt and $lt. This allows you to match documents where at least one array element satisfies all specified conditions.

Syntax

db.collectionName.find({
    arrayFieldName: {
        $elemMatch: {
            $gt: lowerValue,
            $lt: upperValue
        }
    }
});

Sample Data

Let's create a collection with student records containing marks arrays ?

db.findValueInArrayWithMultipleCriteriaDemo.insertMany([
    {
        "StudentName": "Larry",
        "StudentMarks": [-150, 150]
    },
    {
        "StudentName": "Mike", 
        "StudentMarks": [19]
    }
]);

{
    "acknowledged": true,
    "insertedIds": [
        ObjectId("5c77daf6fc4e719b197a12f5"),
        ObjectId("5c77db09fc4e719b197a12f6")
    ]
}

View Sample Data

db.findValueInArrayWithMultipleCriteriaDemo.find();

{
    "_id": ObjectId("5c77daf6fc4e719b197a12f5"),
    "StudentName": "Larry",
    "StudentMarks": [-150, 150]
}
{
    "_id": ObjectId("5c77db09fc4e719b197a12f6"),
    "StudentName": "Mike",
    "StudentMarks": [19]
}

Example: Find Students with Marks Between -20 and 20

Find students who have at least one mark greater than -20 and less than 20 ?

db.findValueInArrayWithMultipleCriteriaDemo.find({
    StudentMarks: {
        $elemMatch: {
            $gt: -20,
            $lt: 20
        }
    }
});

{
    "_id": ObjectId("5c77db09fc4e719b197a12f6"),
    "StudentName": "Mike",
    "StudentMarks": [19]
}

Key Points

• $elemMatch ensures all conditions are satisfied by the same array element
• Larry's document is excluded because neither -150 nor 150 falls within the -20 to 20 range
• Mike's document matches because 19 satisfies both conditions (> -20 AND

Conclusion

Use $elemMatch with multiple comparison operators to find documents where array elements meet all specified criteria simultaneously. This is essential when you need precise matching within individual array elements rather than across the entire array.