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Project Fields to Return from Query

On this page

  • Return All Fields in Matching Documents
  • Return the Specified Fields and the _id Field Only
  • Suppress _id Field
  • Return All But the Excluded Fields
  • Return Specific Fields in Embedded Documents
  • Suppress Specific Fields in Embedded Documents
  • Projection on Embedded Documents in an Array
  • Project Specific Array Elements in the Returned Array
  • Project Fields with Aggregation Expressions
  • Additional Considerations

➤ Use the Select your language drop-down menu in the upper-right to set the language of the following examples.


By default, queries in MongoDB return all fields in matching documents. To limit the amount of data that MongoDB sends to applications, you can include a projection document to specify or restrict fields to return.

This page provides examples of query operations with projection using MongoDB Compass.

The examples on this page use the inventory collection. Connect to a test database in your MongoDB instance then create the inventory collection:

This page provides examples of query operations with projection using the MongoCollection.Find() method in the MongoDB C# Driver.

The examples on this page use the inventory collection. Connect to a test database in your MongoDB instance then create the inventory collection:

This page provides examples of query operations with projection using the Collection.Find function in the MongoDB Go Driver.

The examples on this page use the inventory collection. Connect to a test database in your MongoDB instance then create the inventory collection:

This page provides examples of query operations with projection using the com.mongodb.reactivestreams.client.MongoCollection.find method in the MongoDB Java Reactive Streams Driver.

The examples on this page use the inventory collection. Connect to a test database in your MongoDB instance then create the inventory collection:

This page provides examples of query operations with projection using the com.mongodb.client.MongoCollection.find method in the MongoDB Java Synchronous Driver.

Tip

The driver provides com.mongodb.client.model.Filters helper methods to facilitate the creation of filter documents. The examples on this page use these methods to create the filter documents.

The examples on this page use the inventory collection. Connect to a test database in your MongoDB instance then create the inventory collection:

This page provides examples of query operations with projection using the motor.motor_asyncio.AsyncIOMotorCollection.find method in the Motor driver.

The examples on this page use the inventory collection. Connect to a test database in your MongoDB instance then create the inventory collection:

This page provides examples of query operations with projection using the Collection.find() method in the MongoDB Node.js Driver.

The examples on this page use the inventory collection. Connect to a test database in your MongoDB instance then create the inventory collection:

This page provides examples of query operations with projection using the MongoDB::Collection::find() method in the MongoDB Perl Driver.

The examples on this page use the inventory collection. Connect to a test database in your MongoDB instance then create the inventory collection:

This page provides examples of query operations with projection using the MongoDB\\Collection::find() method in the MongoDB PHP Library.

The examples on this page use the inventory collection. Connect to a test database in your MongoDB instance then create the inventory collection:

This page provides examples of query operations with projection using the pymongo.collection.Collection.find method in the PyMongo Python driver.

The examples on this page use the inventory collection. Connect to a test database in your MongoDB instance then create the inventory collection:

This page provides examples of query operations with projection using the Mongo::Collection#find() method in the MongoDB Ruby Driver.

The examples on this page use the inventory collection. Connect to a test database in your MongoDB instance then create the inventory collection:

This page provides examples of query operations with projection using the collection.find() method in the MongoDB Scala Driver.

The examples on this page use the inventory collection. Connect to a test database in your MongoDB instance then create the inventory collection:

db.inventory.insertMany( [
{ item: "journal", status: "A", size: { h: 14, w: 21, uom: "cm" }, instock: [ { warehouse: "A", qty: 5 } ] },
{ item: "notebook", status: "A", size: { h: 8.5, w: 11, uom: "in" }, instock: [ { warehouse: "C", qty: 5 } ] },
{ item: "paper", status: "D", size: { h: 8.5, w: 11, uom: "in" }, instock: [ { warehouse: "A", qty: 60 } ] },
{ item: "planner", status: "D", size: { h: 22.85, w: 30, uom: "cm" }, instock: [ { warehouse: "A", qty: 40 } ] },
{ item: "postcard", status: "A", size: { h: 10, w: 15.25, uom: "cm" }, instock: [ { warehouse: "B", qty: 15 }, { warehouse: "C", qty: 35 } ] }
]);
[
{ "item": "journal", "status": "A", "size": { "h": 14, "w": 21, "uom": "cm" }, "instock": [ { "warehouse": "A", "qty": 5 } ] },
{ "item": "notebook", "status": "A", "size": { "h": 8.5, "w": 11, "uom": "in" }, "instock": [ { "warehouse": "C", "qty": 5 } ] },
{ "item": "paper", "status": "D", "size": { "h": 8.5, "w": 11, "uom": "in" }, "instock": [ { "warehouse": "A", "qty": 60 } ] },
{ "item": "planner", "status": "D", "size": { "h": 22.85, "w": 30, "uom": "cm" }, "instock": [ { "warehouse": "A", "qty": 40 } ] },
{ "item": "postcard", "status": "A", "size": { "h": 10, "w": 15.25, "uom": "cm" }, "instock": [ { "warehouse": "B", "qty": 15 }, { "warehouse": "C", "qty": 35 } ] }
]

For instructions on inserting documents in MongoDB Compass, see Insert Documents.

var documents = new[]
{
new BsonDocument
{
{ "item", "journal" },
{ "status", "A" },
{ "size", new BsonDocument { { "h", 14 }, { "w", 21 }, { "uom", "cm" } } },
{ "instock", new BsonArray
{
new BsonDocument { { "warehouse", "A" }, { "qty", 5 } } }
}
},
new BsonDocument
{
{ "item", "notebook" },
{ "status", "A" },
{ "size", new BsonDocument { { "h", 8.5 }, { "w", 11 }, { "uom", "in" } } },
{ "instock", new BsonArray
{
new BsonDocument { { "warehouse", "C" }, { "qty", 5 } } }
}
},
new BsonDocument
{
{ "item", "paper" },
{ "status", "D" },
{ "size", new BsonDocument { { "h", 8.5 }, { "w", 11 }, { "uom", "in" } } },
{ "instock", new BsonArray
{
new BsonDocument { { "warehouse", "A" }, { "qty", 60 } } }
}
},
new BsonDocument
{
{ "item", "planner" },
{ "status", "D" },
{ "size", new BsonDocument { { "h", 22.85 }, { "w", 30 }, { "uom", "cm" } } },
{ "instock", new BsonArray
{
new BsonDocument { { "warehouse", "A" }, { "qty", 40 } } }
}
},
new BsonDocument
{
{ "item", "postcard" },
{ "status", "A" },
{ "size", new BsonDocument { { "h", 10 }, { "w", 15.25 }, { "uom", "cm" } } },
{ "instock", new BsonArray
{
new BsonDocument { { "warehouse", "B" }, { "qty", 15 } },
new BsonDocument { { "warehouse", "C" }, { "qty", 35 } } }
}
}
};
collection.InsertMany(documents);
docs := []interface{}{
bson.D{
{"item", "journal"},
{"status", "A"},
{"size", bson.D{
{"h", 14},
{"w", 21},
{"uom", "cm"},
}},
{"instock", bson.A{
bson.D{
{"warehouse", "A"},
{"qty", 5},
},
}},
},
bson.D{
{"item", "notebook"},
{"status", "A"},
{"size", bson.D{
{"h", 8.5},
{"w", 11},
{"uom", "in"},
}},
{"instock", bson.A{
bson.D{
{"warehouse", "EC"},
{"qty", 5},
},
}},
},
bson.D{
{"item", "paper"},
{"status", "D"},
{"size", bson.D{
{"h", 8.5},
{"w", 11},
{"uom", "in"},
}},
{"instock", bson.A{
bson.D{
{"warehouse", "A"},
{"qty", 60},
},
}},
},
bson.D{
{"item", "planner"},
{"status", "D"},
{"size", bson.D{
{"h", 22.85},
{"w", 30},
{"uom", "cm"},
}},
{"instock", bson.A{
bson.D{
{"warehouse", "A"},
{"qty", 40},
},
}},
},
bson.D{
{"item", "postcard"},
{"status", "A"},
{"size", bson.D{
{"h", 10},
{"w", 15.25},
{"uom", "cm"},
}},
{"instock", bson.A{
bson.D{
{"warehouse", "B"},
{"qty", 15},
},
bson.D{
{"warehouse", "EC"},
{"qty", 35},
},
}},
},
}
result, err := coll.InsertMany(context.TODO(), docs)
Publisher<Success> insertManyPublisher = collection.insertMany(asList(
Document.parse("{ item: 'journal', status: 'A', size: { h: 14, w: 21, uom: 'cm' }, instock: [ { warehouse: 'A', qty: 5 }]}"),
Document.parse("{ item: 'notebook', status: 'A', size: { h: 8.5, w: 11, uom: 'in' }, instock: [ { warehouse: 'C', qty: 5}]}"),
Document.parse("{ item: 'paper', status: 'D', size: { h: 8.5, w: 11, uom: 'in' }, instock: [ { warehouse: 'A', qty: 60 }]}"),
Document.parse("{ item: 'planner', status: 'D', size: { h: 22.85, w: 30, uom: 'cm' }, instock: [ { warehouse: 'A', qty: 40}]}"),
Document.parse("{ item: 'postcard', status: 'A', size: { h: 10, w: 15.25, uom: 'cm' }, "
+ "instock: [ { warehouse: 'B', qty: 15 }, { warehouse: 'C', qty: 35 } ] }")
));
collection.insertMany(asList(
Document.parse("{ item: 'journal', status: 'A', size: { h: 14, w: 21, uom: 'cm' }, instock: [ { warehouse: 'A', qty: 5 }]}"),
Document.parse("{ item: 'notebook', status: 'A', size: { h: 8.5, w: 11, uom: 'in' }, instock: [ { warehouse: 'C', qty: 5}]}"),
Document.parse("{ item: 'paper', status: 'D', size: { h: 8.5, w: 11, uom: 'in' }, instock: [ { warehouse: 'A', qty: 60 }]}"),
Document.parse("{ item: 'planner', status: 'D', size: { h: 22.85, w: 30, uom: 'cm' }, instock: [ { warehouse: 'A', qty: 40}]}"),
Document.parse("{ item: 'postcard', status: 'A', size: { h: 10, w: 15.25, uom: 'cm' }, "
+ "instock: [ { warehouse: 'B', qty: 15 }, { warehouse: 'C', qty: 35 } ] }")
));
await db.inventory.insert_many(
[
{
"item": "journal",
"status": "A",
"size": {"h": 14, "w": 21, "uom": "cm"},
"instock": [{"warehouse": "A", "qty": 5}],
},
{
"item": "notebook",
"status": "A",
"size": {"h": 8.5, "w": 11, "uom": "in"},
"instock": [{"warehouse": "C", "qty": 5}],
},
{
"item": "paper",
"status": "D",
"size": {"h": 8.5, "w": 11, "uom": "in"},
"instock": [{"warehouse": "A", "qty": 60}],
},
{
"item": "planner",
"status": "D",
"size": {"h": 22.85, "w": 30, "uom": "cm"},
"instock": [{"warehouse": "A", "qty": 40}],
},
{
"item": "postcard",
"status": "A",
"size": {"h": 10, "w": 15.25, "uom": "cm"},
"instock": [{"warehouse": "B", "qty": 15}, {"warehouse": "C", "qty": 35}],
},
]
)
await db.collection('inventory').insertMany([
{
item: 'journal',
status: 'A',
size: { h: 14, w: 21, uom: 'cm' },
instock: [{ warehouse: 'A', qty: 5 }]
},
{
item: 'notebook',
status: 'A',
size: { h: 8.5, w: 11, uom: 'in' },
instock: [{ warehouse: 'C', qty: 5 }]
},
{
item: 'paper',
status: 'D',
size: { h: 8.5, w: 11, uom: 'in' },
instock: [{ warehouse: 'A', qty: 60 }]
},
{
item: 'planner',
status: 'D',
size: { h: 22.85, w: 30, uom: 'cm' },
instock: [{ warehouse: 'A', qty: 40 }]
},
{
item: 'postcard',
status: 'A',
size: { h: 10, w: 15.25, uom: 'cm' },
instock: [
{ warehouse: 'B', qty: 15 },
{ warehouse: 'C', qty: 35 }
]
}
]);
$db->coll("inventory")->insert_many(
[
{
item => "journal",
status => "A",
size => { h => 14, w => 21, uom => "cm" },
instock => [ { warehouse => "A", qty => 5 } ]
},
{
item => "notebook",
status => "A",
size => { h => 8.5, w => 11, uom => "in" },
instock => [ { warehouse => "C", qty => 5 } ]
},
{
item => "paper",
status => "D",
size => { h => 8.5, w => 11, uom => "in" },
instock => [ { warehouse => "A", qty => 60 } ]
},
{
item => "planner",
status => "D",
size => { h => 22.85, w => 30, uom => "cm" },
instock => [ { warehouse => "A", qty => 40 } ]
},
{
item => "postcard",
status => "A",
size => { h => 10, w => 15.25, uom => "cm" },
instock => [
{ warehouse => "B", qty => 15 },
{ warehouse => "C", qty => 35 }
]
}
]
);
$insertManyResult = $db->inventory->insertMany([
[
'item' => 'journal',
'status' => 'A',
'size' => ['h' => 14, 'w' => 21, 'uom' => 'cm'],
'instock' => [
['warehouse' => 'A', 'qty' => 5],
],
],
[
'item' => 'notebook',
'status' => 'A',
'size' => ['h' => 8.5, 'w' => 11, 'uom' => 'in'],
'instock' => [
['warehouse' => 'C', 'qty' => 5],
],
],
[
'item' => 'paper',
'status' => 'D',
'size' => ['h' => 8.5, 'w' => 11, 'uom' => 'in'],
'instock' => [
['warehouse' => 'A', 'qty' => 60],
],
],
[
'item' => 'planner',
'status' => 'D',
'size' => ['h' => 22.85, 'w' => 30, 'uom' => 'cm'],
'instock' => [
['warehouse' => 'A', 'qty' => 40],
],
],
[
'item' => 'postcard',
'status' => 'A',
'size' => ['h' => 10, 'w' => 15.25, 'uom' => 'cm'],
'instock' => [
['warehouse' => 'B', 'qty' => 15],
['warehouse' => 'C', 'qty' => 35],
],
],
]);
db.inventory.insert_many(
[
{
"item": "journal",
"status": "A",
"size": {"h": 14, "w": 21, "uom": "cm"},
"instock": [{"warehouse": "A", "qty": 5}],
},
{
"item": "notebook",
"status": "A",
"size": {"h": 8.5, "w": 11, "uom": "in"},
"instock": [{"warehouse": "C", "qty": 5}],
},
{
"item": "paper",
"status": "D",
"size": {"h": 8.5, "w": 11, "uom": "in"},
"instock": [{"warehouse": "A", "qty": 60}],
},
{
"item": "planner",
"status": "D",
"size": {"h": 22.85, "w": 30, "uom": "cm"},
"instock": [{"warehouse": "A", "qty": 40}],
},
{
"item": "postcard",
"status": "A",
"size": {"h": 10, "w": 15.25, "uom": "cm"},
"instock": [{"warehouse": "B", "qty": 15}, {"warehouse": "C", "qty": 35}],
},
]
)
client[:inventory].insert_many([{ item: 'journal',
status: 'A',
size: { h: 14, w: 21, uom: 'cm' },
instock: [ { warehouse: 'A', qty: 5 }] },
{ item: 'notebook',
status: 'A',
size: { h: 8.5, w: 11, uom: 'in' },
instock: [ { warehouse: 'C', qty: 5 }] },
{ item: 'paper',
status: 'D',
size: { h: 8.5, w: 11, uom: 'in' },
instock: [ { warehouse: 'A', qty: 60 }] },
{ item: 'planner',
status: 'D',
size: { h: 22.85, w: 30, uom: 'cm' },
instock: [ { warehouse: 'A', qty: 40 }] },
{ item: 'postcard',
status: 'A',
size: { h: 10, w: 15.25, uom: 'cm' },
instock: [ { warehouse: 'B', qty: 15 },
{ warehouse: 'C', qty: 35 }] }])
collection.insertMany(Seq(
Document("""{ item: "journal", status: "A", size: { h: 14, w: 21, uom: "cm" }, instock: [ { warehouse: "A", qty: 5 } ] }"""),
Document("""{ item: "notebook", status: "A", size: { h: 8.5, w: 11, uom: "in" }, instock: [ { warehouse: "C", qty: 5 } ] }"""),
Document("""{ item: "paper", status: "D", size: { h: 8.5, w: 11, uom: "in" }, instock: [ { warehouse: "A", qty: 60 } ] }"""),
Document("""{ item: "planner", status: "D", size: { h: 22.85, w: 30, uom: "cm" }, instock: [ { warehouse: "A", qty: 40 } ] }"""),
Document("""{ item: "postcard", status: "A", size: { h: 10, w: 15.25, uom: "cm" },
instock: [ { warehouse: "B", qty: 15 }, { warehouse: "C", qty: 35 } ] }""")
)).execute()

If you do not specify a projection document, the db.collection.find() method returns all fields in the matching documents.

If you do not specify a projection document, Compass returns all fields in the matching documents.

If you do not specify a projection filter, the MongoCollection.Find() method returns all fields in the matching documents.

If you do not specify a projection, the com.mongodb.reactivestreams.client.MongoCollection.find method returns all fields in the matching documents.

If you do not specify a projection, the com.mongodb.client.MongoCollection.find method returns all fields in the matching documents.

If you do not specify a projection document, the find() method yields all fields in the matching documents.

If you do not specify a projection document, the find() method returns all fields in the matching documents.

If you do not specify a projection document, the find() method returns all fields in the matching documents.

If you do not specify a projection document, the find method returns all fields in the matching documents.

If you do not specify a projection document, the find() method returns all fields in the matching documents.

If you do not specify a projection, the collection.find() method returns all fields in the matching documents.

The following example returns all fields from all documents in the inventory collection where the status equals "A":

db.inventory.find( { status: "A" } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var result = collection.Find(filter).ToList();
cursor, err := coll.Find(
context.TODO(),
bson.D{{"status", "A"}},
)
FindPublisher<Document> findPublisher = collection.find(eq("status", "A"));
FindIterable<Document> findIterable = collection.find(eq("status", "A"));
cursor = db.inventory.find({"status": "A"})
const cursor = db.collection('inventory').find({
status: 'A'
});
$cursor = $db->coll("inventory")->find( { status => "A" } );
$cursor = $db->inventory->find(['status' => 'A']);
cursor = db.inventory.find({"status": "A"})
client[:inventory].find(status: 'A')
var findObservable = collection.find(equal("status", "A"))

The operation corresponds to the following SQL statement:

SELECT * from inventory WHERE status = "A"

A projection can explicitly include several fields by setting the <field> to 1 in the projection document. The following operation returns all documents that match the query. In the result set, only the item, status and, by default, the _id fields return in the matching documents.

db.inventory.find( { status: "A" }, { item: 1, status: 1 } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { item: 1, status: 1 }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Include("item").Include("status");
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"item", 1},
{"status", 1},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A")).projection(include("item", "status"));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A")).projection(include("item", "status"));
cursor = db.inventory.find({"status": "A"}, {"item": 1, "status": 1})
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ item: 1, status: 1 });
$cursor = $db->coll("inventory")->find(
{ status => "A" }, { projection => { item => 1, status => 1 } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['item' => 1, 'status' => 1]],
);
cursor = db.inventory.find({"status": "A"}, {"item": 1, "status": 1})
client[:inventory].find({ status: 'A' },
projection: { item: 1, status: 1 })
findObservable = collection.find(equal("status", "A")).projection(include("item", "status"))

The operation corresponds to the following SQL statement:

SELECT _id, item, status from inventory WHERE status = "A"

You can remove the _id field from the results by setting it to 0 in the projection, as in the following example:

db.inventory.find( { status: "A" }, { item: 1, status: 1, _id: 0 } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { item: 1, status: 1, _id: 0 }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Include("item").Include("status").Exclude("_id");
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"item", 1},
{"status", 1},
{"_id", 0},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), excludeId()));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), excludeId()));
cursor = db.inventory.find({"status": "A"}, {"item": 1, "status": 1, "_id": 0})
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ item: 1, status: 1, _id: 0 });
$cursor = $db->coll("inventory")->find(
{ status => "A" }, { projection => { item => 1, status => 1, "_id" => 0 } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['item' => 1, 'status' => 1, '_id' => 0]],
);
cursor = db.inventory.find({"status": "A"}, {"item": 1, "status": 1, "_id": 0})
client[:inventory].find({ status: 'A' },
projection: { item: 1, status: 1, _id: 0 })
findObservable = collection.find(equal("status", "A"))
.projection(fields(include("item", "status"), excludeId()))

The operation corresponds to the following SQL statement:

SELECT item, status from inventory WHERE status = "A"

Note

With the exception of the _id field, you cannot combine inclusion and exclusion statements in projection documents.

Instead of listing the fields to return in the matching document, you can use a projection to exclude specific fields. The following example which returns all fields except for the status and the instock fields in the matching documents:

db.inventory.find( { status: "A" }, { status: 0, instock: 0 } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { status: 0, instock: 0 }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Exclude("status").Exclude("instock");
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"status", 0},
{"instock", 0},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A")).projection(exclude("item", "status"));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A")).projection(exclude("item", "status"));
cursor = db.inventory.find({"status": "A"}, {"status": 0, "instock": 0})
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ status: 0, instock: 0 });
$cursor = $db->coll("inventory")->find(
{ status => "A" }, { projection => { status => 0, instock => 0 } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['status' => 0, 'instock' => 0]],
);
cursor = db.inventory.find({"status": "A"}, {"status": 0, "instock": 0})
client[:inventory].find({ status: 'A' },
projection: { status: 0, instock: 0 })
findObservable = collection.find(equal("status", "A")).projection(exclude("item", "status"))

Note

With the exception of the _id field, you cannot combine inclusion and exclusion statements in projection documents.

You can return specific fields in an embedded document. Use the dot notation to refer to the embedded field and set to 1 in the projection document.

The following example returns:

  • The _id field (returned by default),

  • The item field,

  • The status field,

  • The uom field in the size document.

The uom field remains embedded in the size document.

db.inventory.find(
{ status: "A" },
{ item: 1, status: 1, "size.uom": 1 }
)
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { item: 1, status: 1, "size.uom": 1 }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Include("item").Include("status").Include("size.uom");
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"item", 1},
{"status", 1},
{"size.uom", 1},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A")).projection(include("item", "status", "size.uom"));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A")).projection(include("item", "status", "size.uom"));
cursor = db.inventory.find({"status": "A"}, {"item": 1, "status": 1, "size.uom": 1})
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ item: 1, status: 1, 'size.uom': 1 });
$cursor = $db->coll("inventory")->find(
{ status => "A" }, { projection => { item => 1, status => 1, "size.uom" => 1 } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['item' => 1, 'status' => 1, 'size.uom' => 1]],
);
cursor = db.inventory.find({"status": "A"}, {"item": 1, "status": 1, "size.uom": 1})
client[:inventory].find({ status: 'A' },
projection: { 'item' => 1, 'status' => 1, 'size.uom' => 1 })
findObservable = collection.find(equal("status", "A")).projection(include("item", "status", "size.uom"))

Starting in MongoDB 4.4, you can also specify embedded fields using the nested form, e.g. { item: 1, status: 1, size: { uom: 1 } }.

You can suppress specific fields in an embedded document. Use the dot notation to refer to the embedded field in the projection document and set to 0.

The following example specifies a projection to exclude the uom field inside the size document. All other fields are returned in the matching documents:

db.inventory.find(
{ status: "A" },
{ "size.uom": 0 }
)
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { "size.uom": 0 }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Exclude("size.uom");
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"size.uom", 0},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A")).projection(exclude("size.uom"));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A")).projection(exclude("size.uom"));
cursor = db.inventory.find({"status": "A"}, {"size.uom": 0})
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ 'size.uom': 0 });
$cursor = $db->coll("inventory")->find(
{ status => "A" }, { projection => { "size.uom" => 0 } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['size.uom' => 0]],
);
cursor = db.inventory.find({"status": "A"}, {"size.uom": 0})
client[:inventory].find({ status: 'A' },
projection: { 'size.uom' => 0 })
findObservable = collection.find(equal("status", "A")).projection(exclude("size.uom"))

Starting in MongoDB 4.4, you can also specify embedded fields using the nested form, e.g. { size: { uom: 0 } }.

Use dot notation to project specific fields inside documents embedded in an array.

The following example specifies a projection to return:

  • The _id field (returned by default),

  • The item field,

  • The status field,

  • The qty field in the documents embedded in the instock array.

db.inventory.find( { status: "A" }, { item: 1, status: 1, "instock.qty": 1 } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { item: 1, status: 1, "instock.qty": 1 }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Include("item").Include("status").Include("instock.qty");
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"item", 1},
{"status", 1},
{"instock.qty", 1},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A")).projection(include("item", "status", "instock.qty"));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A")).projection(include("item", "status", "instock.qty"));
cursor = db.inventory.find({"status": "A"}, {"item": 1, "status": 1, "instock.qty": 1})
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ item: 1, status: 1, 'instock.qty': 1 });
$cursor = $db->coll("inventory")->find( { status => "A" },
{ projection => { item => 1, status => 1, "instock.qty" => 1 } } );
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['item' => 1, 'status' => 1, 'instock.qty' => 1]],
);
cursor = db.inventory.find({"status": "A"}, {"item": 1, "status": 1, "instock.qty": 1})
client[:inventory].find({ status: 'A' },
projection: {'item' => 1, 'status' => 1, 'instock.qty' => 1 })
findObservable = collection.find(equal("status", "A")).projection(include("item", "status", "instock.qty"))

For fields that contain arrays, MongoDB provides the following projection operators for manipulating arrays: $elemMatch, $slice, and $.

The following example uses the $slice projection operator to return the last element in the instock array:

db.inventory.find( { status: "A" }, { item: 1, status: 1, instock: { $slice: -1 } } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { item: 1, status: 1, instock: { $slice: -1 } }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Include("item").Include("status").Slice("instock", -1);
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"item", 1},
{"status", 1},
{"instock", bson.D{
{"$slice", -1},
}},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ item: 1, status: 1, instock: { $slice: -1 } });
$cursor = $db->coll("inventory")->find(
{ status => "A" },
{ projection => { item => 1, status => 1, instock => { '$slice' => -1 } } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['item' => 1, 'status' => 1, 'instock' => ['$slice' => -1]]],
);
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
client[:inventory].find({ status: 'A' },
projection: {'item' => 1,
'status' => 1,
'instock' => { '$slice' => -1 } })
findObservable = collection.find(equal("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)))

$elemMatch, $slice, and $ are the only way to project specific elements to include in the returned array. For instance, you cannot project specific array elements using the array index; e.g. { "instock.0": 1 } projection will not project the array with the first element.

For fields that contain arrays, MongoDB provides the following projection operators for manipulating arrays: $elemMatch, $slice, and $.

The following example uses the $slice projection operator to return the last element in the instock array:

db.inventory.find( { status: "A" }, { item: 1, status: 1, instock: { $slice: -1 } } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { item: 1, status: 1, instock: { $slice: -1 } }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Include("item").Include("status").Slice("instock", -1);
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"item", 1},
{"status", 1},
{"instock", bson.D{
{"$slice", -1},
}},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ item: 1, status: 1, instock: { $slice: -1 } });
$cursor = $db->coll("inventory")->find(
{ status => "A" },
{ projection => { item => 1, status => 1, instock => { '$slice' => -1 } } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['item' => 1, 'status' => 1, 'instock' => ['$slice' => -1]]],
);
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
client[:inventory].find({ status: 'A' },
projection: {'item' => 1,
'status' => 1,
'instock' => { '$slice' => -1 } })
findObservable = collection.find(equal("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)))

For fields that contain arrays, MongoDB provides the following projection operators for manipulating arrays: $elemMatch, $slice, and $.

The following example uses the $slice projection operator to return the last element in the instock array:

db.inventory.find( { status: "A" }, { item: 1, status: 1, instock: { $slice: -1 } } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { item: 1, status: 1, instock: { $slice: -1 } }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Include("item").Include("status").Slice("instock", -1);
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"item", 1},
{"status", 1},
{"instock", bson.D{
{"$slice", -1},
}},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ item: 1, status: 1, instock: { $slice: -1 } });
$cursor = $db->coll("inventory")->find(
{ status => "A" },
{ projection => { item => 1, status => 1, instock => { '$slice' => -1 } } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['item' => 1, 'status' => 1, 'instock' => ['$slice' => -1]]],
);
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
client[:inventory].find({ status: 'A' },
projection: {'item' => 1,
'status' => 1,
'instock' => { '$slice' => -1 } })
findObservable = collection.find(equal("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)))

$elemMatch, $slice, and $ are the only way to project specific elements to include in the returned array.

For example, the following operation will not project the array with the first element:

Builders<BsonDocument>.Projection.Include("instock.0")

For fields that contain arrays, MongoDB provides the following projection operators for manipulating arrays: $elemMatch, $slice, and $.

The following example uses the $slice projection operator to return the last element in the instock array:

db.inventory.find( { status: "A" }, { item: 1, status: 1, instock: { $slice: -1 } } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { item: 1, status: 1, instock: { $slice: -1 } }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Include("item").Include("status").Slice("instock", -1);
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"item", 1},
{"status", 1},
{"instock", bson.D{
{"$slice", -1},
}},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ item: 1, status: 1, instock: { $slice: -1 } });
$cursor = $db->coll("inventory")->find(
{ status => "A" },
{ projection => { item => 1, status => 1, instock => { '$slice' => -1 } } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['item' => 1, 'status' => 1, 'instock' => ['$slice' => -1]]],
);
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
client[:inventory].find({ status: 'A' },
projection: {'item' => 1,
'status' => 1,
'instock' => { '$slice' => -1 } })
findObservable = collection.find(equal("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)))

$elemMatch, $slice, and $ are the only way to project specific elements to include in the returned array. For instance, you cannot project specific array elements using the array index; e.g. include("instock.0") projection will not project the array with the first element.

For fields that contain arrays, MongoDB provides the following projection operators for manipulating arrays: $elemMatch, $slice, and $.

The following example uses the $slice projection operator to return the last element in the instock array:

db.inventory.find( { status: "A" }, { item: 1, status: 1, instock: { $slice: -1 } } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { item: 1, status: 1, instock: { $slice: -1 } }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Include("item").Include("status").Slice("instock", -1);
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"item", 1},
{"status", 1},
{"instock", bson.D{
{"$slice", -1},
}},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ item: 1, status: 1, instock: { $slice: -1 } });
$cursor = $db->coll("inventory")->find(
{ status => "A" },
{ projection => { item => 1, status => 1, instock => { '$slice' => -1 } } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['item' => 1, 'status' => 1, 'instock' => ['$slice' => -1]]],
);
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
client[:inventory].find({ status: 'A' },
projection: {'item' => 1,
'status' => 1,
'instock' => { '$slice' => -1 } })
findObservable = collection.find(equal("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)))

$elemMatch, $slice, and $ are the only way to project specific elements to include in the returned array. For instance, you cannot project specific array elements using the array index; e.g. include("instock.0") projection will not project the array with the first element.

For fields that contain arrays, MongoDB provides the following projection operators for manipulating arrays: $elemMatch, $slice, and $.

The following example uses the $slice projection operator to return the last element in the instock array:

db.inventory.find( { status: "A" }, { item: 1, status: 1, instock: { $slice: -1 } } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { item: 1, status: 1, instock: { $slice: -1 } }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Include("item").Include("status").Slice("instock", -1);
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"item", 1},
{"status", 1},
{"instock", bson.D{
{"$slice", -1},
}},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ item: 1, status: 1, instock: { $slice: -1 } });
$cursor = $db->coll("inventory")->find(
{ status => "A" },
{ projection => { item => 1, status => 1, instock => { '$slice' => -1 } } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['item' => 1, 'status' => 1, 'instock' => ['$slice' => -1]]],
);
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
client[:inventory].find({ status: 'A' },
projection: {'item' => 1,
'status' => 1,
'instock' => { '$slice' => -1 } })
findObservable = collection.find(equal("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)))

$elemMatch, $slice, and $ are the only way to project specific elements to include in the returned array. For instance, you cannot project specific array elements using the array index; e.g. include("instock.0") projection will not project the array with the first element.

For fields that contain arrays, MongoDB provides the following projection operators for manipulating arrays: $elemMatch, $slice, and $.

The following example uses the $slice projection operator to return the last element in the instock array:

db.inventory.find( { status: "A" }, { item: 1, status: 1, instock: { $slice: -1 } } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { item: 1, status: 1, instock: { $slice: -1 } }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Include("item").Include("status").Slice("instock", -1);
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"item", 1},
{"status", 1},
{"instock", bson.D{
{"$slice", -1},
}},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ item: 1, status: 1, instock: { $slice: -1 } });
$cursor = $db->coll("inventory")->find(
{ status => "A" },
{ projection => { item => 1, status => 1, instock => { '$slice' => -1 } } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['item' => 1, 'status' => 1, 'instock' => ['$slice' => -1]]],
);
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
client[:inventory].find({ status: 'A' },
projection: {'item' => 1,
'status' => 1,
'instock' => { '$slice' => -1 } })
findObservable = collection.find(equal("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)))

$elemMatch, $slice, and $ are the only way to project specific elements to include in the returned array. For instance, you cannot project specific array elements using the array index; e.g. { "instock.0": 1 } projection will not project the array with the first element.

For fields that contain arrays, MongoDB provides the following projection operators for manipulating arrays: $elemMatch, $slice, and $.

The following example uses the $slice projection operator to return the last element in the instock array:

db.inventory.find( { status: "A" }, { item: 1, status: 1, instock: { $slice: -1 } } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { item: 1, status: 1, instock: { $slice: -1 } }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Include("item").Include("status").Slice("instock", -1);
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"item", 1},
{"status", 1},
{"instock", bson.D{
{"$slice", -1},
}},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ item: 1, status: 1, instock: { $slice: -1 } });
$cursor = $db->coll("inventory")->find(
{ status => "A" },
{ projection => { item => 1, status => 1, instock => { '$slice' => -1 } } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['item' => 1, 'status' => 1, 'instock' => ['$slice' => -1]]],
);
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
client[:inventory].find({ status: 'A' },
projection: {'item' => 1,
'status' => 1,
'instock' => { '$slice' => -1 } })
findObservable = collection.find(equal("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)))

$elemMatch, $slice, and $ are the only way to project specific elements to include in the returned array. For instance, you cannot project specific array elements using the array index; e.g. { "instock.0" => 1 } projection will not project the array with the first element.

For fields that contain arrays, MongoDB provides the following projection operators for manipulating arrays: $elemMatch, $slice, and $.

The following example uses the $slice projection operator to return the last element in the instock array:

db.inventory.find( { status: "A" }, { item: 1, status: 1, instock: { $slice: -1 } } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { item: 1, status: 1, instock: { $slice: -1 } }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Include("item").Include("status").Slice("instock", -1);
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"item", 1},
{"status", 1},
{"instock", bson.D{
{"$slice", -1},
}},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ item: 1, status: 1, instock: { $slice: -1 } });
$cursor = $db->coll("inventory")->find(
{ status => "A" },
{ projection => { item => 1, status => 1, instock => { '$slice' => -1 } } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['item' => 1, 'status' => 1, 'instock' => ['$slice' => -1]]],
);
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
client[:inventory].find({ status: 'A' },
projection: {'item' => 1,
'status' => 1,
'instock' => { '$slice' => -1 } })
findObservable = collection.find(equal("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)))

$elemMatch, $slice, and $ are the only way to project specific elements to include in the returned array. For instance, you cannot project specific array elements using the array index; e.g. [ "instock.0" => 1 ] projection will not project the array with the first element.

For fields that contain arrays, MongoDB provides the following projection operators for manipulating arrays: $elemMatch, $slice, and $.

The following example uses the $slice projection operator to return the last element in the instock array:

db.inventory.find( { status: "A" }, { item: 1, status: 1, instock: { $slice: -1 } } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { item: 1, status: 1, instock: { $slice: -1 } }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Include("item").Include("status").Slice("instock", -1);
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"item", 1},
{"status", 1},
{"instock", bson.D{
{"$slice", -1},
}},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ item: 1, status: 1, instock: { $slice: -1 } });
$cursor = $db->coll("inventory")->find(
{ status => "A" },
{ projection => { item => 1, status => 1, instock => { '$slice' => -1 } } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['item' => 1, 'status' => 1, 'instock' => ['$slice' => -1]]],
);
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
client[:inventory].find({ status: 'A' },
projection: {'item' => 1,
'status' => 1,
'instock' => { '$slice' => -1 } })
findObservable = collection.find(equal("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)))

$elemMatch, $slice, and $ are the only way to project specific elements to include in the returned array. For instance, you cannot project specific array elements using the array index; e.g. { "instock.0": 1 } projection will not project the array with the first element.

For fields that contain arrays, MongoDB provides the following projection operators for manipulating arrays: $elemMatch, $slice, and $.

The following example uses the $slice projection operator to return the last element in the instock array:

db.inventory.find( { status: "A" }, { item: 1, status: 1, instock: { $slice: -1 } } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { item: 1, status: 1, instock: { $slice: -1 } }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Include("item").Include("status").Slice("instock", -1);
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"item", 1},
{"status", 1},
{"instock", bson.D{
{"$slice", -1},
}},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ item: 1, status: 1, instock: { $slice: -1 } });
$cursor = $db->coll("inventory")->find(
{ status => "A" },
{ projection => { item => 1, status => 1, instock => { '$slice' => -1 } } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['item' => 1, 'status' => 1, 'instock' => ['$slice' => -1]]],
);
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
client[:inventory].find({ status: 'A' },
projection: {'item' => 1,
'status' => 1,
'instock' => { '$slice' => -1 } })
findObservable = collection.find(equal("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)))

$elemMatch, $slice, and $ are the only way to project specific elements to include in the returned array. For instance, you cannot project specific array elements using the array index; e.g. { "instock.0" => 1 } projection will not project the array with the first element.

For fields that contain arrays, MongoDB provides the following projection operators for manipulating arrays: $elemMatch, $slice, and $.

The following example uses the $slice projection operator to return the last element in the instock array:

db.inventory.find( { status: "A" }, { item: 1, status: 1, instock: { $slice: -1 } } )
  1. Copy the following expression into the Filter field:

    { status: "A" }
  2. Click Options to open the additional query options.

  3. Copy the following expression into the Project field:

    { item: 1, status: 1, instock: { $slice: -1 } }
  4. Click Find.

var filter = Builders<BsonDocument>.Filter.Eq("status", "A");
var projection = Builders<BsonDocument>.Projection.Include("item").Include("status").Slice("instock", -1);
var result = collection.Find<BsonDocument>(filter).Project(projection).ToList();
projection := bson.D{
{"item", 1},
{"status", 1},
{"instock", bson.D{
{"$slice", -1},
}},
}
cursor, err := coll.Find(
context.TODO(),
bson.D{
{"status", "A"},
},
options.Find().SetProjection(projection),
)
findPublisher = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));

To specify a projection document, chain the com.mongodb.client.FindIterable.projection method to the find method. The example uses the com.mongodb.client.model.Projections class to create the projection documents.

findIterable = collection.find(eq("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)));
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
const cursor = db
.collection('inventory')
.find({
status: 'A'
})
.project({ item: 1, status: 1, instock: { $slice: -1 } });
$cursor = $db->coll("inventory")->find(
{ status => "A" },
{ projection => { item => 1, status => 1, instock => { '$slice' => -1 } } }
);
$cursor = $db->inventory->find(
['status' => 'A'],
['projection' => ['item' => 1, 'status' => 1, 'instock' => ['$slice' => -1]]],
);
cursor = db.inventory.find(
{"status": "A"}, {"item": 1, "status": 1, "instock": {"$slice": -1}}
)
client[:inventory].find({ status: 'A' },
projection: {'item' => 1,
'status' => 1,
'instock' => { '$slice' => -1 } })
findObservable = collection.find(equal("status", "A"))
.projection(fields(include("item", "status"), slice("instock", -1)))

$elemMatch, $slice, and $ are the only way to project specific elements to include in the returned array. For instance, you cannot project specific array elements using the array index; e.g. include("instock.0") projection will not project the array with the first element.

You can specify aggregation expressions in a query projection. Aggregation expressions let you project new fields and modify the values of existing fields.

For example, the following operation uses aggregation expressions to override the value of the status field, and project new fields area and reportNumber.

Note

The following example uses MongoDB Shell syntax. For driver examples of projection with aggregation, see your driver documentation.

db.inventory.find(
{ },
{
_id: 0,
item: 1,
status: {
$switch: {
branches: [
{
case: { $eq: [ "$status", "A" ] },
then: "Available"
},
{
case: { $eq: [ "$status", "D" ] },
then: "Discontinued"
},
],
default: "No status found"
}
},
area: {
$concat: [
{ $toString: { $multiply: [ "$size.h", "$size.w" ] } },
" ",
"$size.uom"
]
},
reportNumber: { $literal: 1 }
}
)
[
{
item: 'journal',
status: 'Available',
area: '294 cm',
reportNumber: 1
},
{
item: 'planner',
status: 'Discontinued',
area: '685.5 cm',
reportNumber: 1
},
{
item: 'notebook',
status: 'Available',
area: '93.5 in',
reportNumber: 1
},
{
item: 'paper',
status: 'Discontinued',
area: '93.5 in',
reportNumber: 1
},
{
item: 'postcard',
status: 'Available',
area: '152.5 cm',
reportNumber: 1
}
]

Starting in MongoDB 4.4, MongoDB enforces additional restrictions with regards to projections. See Projection Restrictions for details.

Tip

See also:

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