Hide id field in MongoDB

To hide the _id field in MongoDB query results, use the projection parameter in the find() method and set _id: 0. This excludes the _id field from the output while displaying other specified fields.

Syntax

db.collection.find(
    { query },
    { _id: 0, "field1": 1, "field2": 1 }
);

Sample Data

db.demo575.insertMany([
    {id: 101, Information: {Name: "Chris", Age: 21}},
    {id: 102, Information: {Name: "David", Age: 20}},
    {id: 101, Information: {Name: "Bob", Age: 23}}
]);

{
    "acknowledged": true,
    "insertedIds": [
        ObjectId("5e916a55581e9acd78b427f7"),
        ObjectId("5e916a5f581e9acd78b427f8"),
        ObjectId("5e916a67581e9acd78b427f9")
    ]
}

Example 1: Display All Fields with _id

db.demo575.find();

{ "_id": ObjectId("5e916a55581e9acd78b427f7"), "id": 101, "Information": { "Name": "Chris", "Age": 21 } }
{ "_id": ObjectId("5e916a5f581e9acd78b427f8"), "id": 102, "Information": { "Name": "David", "Age": 20 } }
{ "_id": ObjectId("5e916a67581e9acd78b427f9"), "id": 101, "Information": { "Name": "Bob", "Age": 23 } }

Example 2: Hide _id Field and Show Specific Fields

db.demo575.find(
    {id: 101},
    {_id: 0, "Information.Name": 1}
);

{ "Information": { "Name": "Chris" } }
{ "Information": { "Name": "Bob" } }

Key Points

• Use _id: 0 in the projection to exclude the _id field from results.
• Combine with fieldName: 1 to include only specific fields you want to see.
• The _id field is included by default in all MongoDB queries unless explicitly excluded.

Conclusion

Set _id: 0 in the projection parameter to hide the _id field from MongoDB query results. This provides cleaner output when you only need specific document fields without the auto-generated ObjectId.