Deleting specific record from an array nested within another array in MongoDB

To delete specific record from an array nested within another array in MongoDB, use the $pull operator combined with the $ positional operator to target the correct parent array element and remove the matching nested document.

Syntax

db.collection.update(
    { "parentArray.field": "matchValue" },
    { $pull: { "parentArray.$.nestedArray": { "field": "valueToDelete" } } }
);

Sample Data

db.demo213.insertOne({
    "id": 101,
    "details1": [
        {
            "Name": "Chris",
            "details2": [
                {
                    "StudentName": "David",
                    "Subject": "MongoDB"
                },
                {
                    "StudentName": "Mike",
                    "Subject": "MySQL"
                }
            ]
        }
    ]
});

{
    "acknowledged": true,
    "insertedId": ObjectId("5e3e300c03d395bdc2134704")
}

Example: Delete Record from Nested Array

Remove the student record with Subject "MySQL" from the nested details2 array ?

db.demo213.update(
    { "id": 101, "details1.Name": "Chris" },
    { $pull: { "details1.$.details2": { "Subject": "MySQL" } } }
);

WriteResult({ "nMatched": 1, "nUpserted": 0, "nModified": 1 })

Verify Result

db.demo213.find().pretty();

{
    "_id": ObjectId("5e3e300c03d395bdc2134704"),
    "id": 101,
    "details1": [
        {
            "Name": "Chris",
            "details2": [
                {
                    "StudentName": "David",
                    "Subject": "MongoDB"
                }
            ]
        }
    ]
}

Key Points

• The $ positional operator identifies the first matching parent array element.
• $pull removes all documents from the nested array that match the specified condition.
• Multiple nested records can be deleted if they match the same criteria.

Conclusion

Use $pull with the $ positional operator to delete specific records from nested arrays. This approach allows precise targeting of nested documents while preserving the overall document structure.