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
- Project Fields to Return from a Query with MongoDB Atlas
- Additional Considerations
You can query embedded documents in MongoDB by using the following methods:
Your programming language's driver.
The MongoDB Atlas UI. To learn more, see Project Fields to Return from a Query with MongoDB Atlas.
➤ Use the Select your language drop-down menu in the upper-right to set the language of the following examples or select MongoDB Compass.
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 the
db.collection.find()
method in mongosh
.
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 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 mongoc_collection_find_with_opts.
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 by using the MongoCollection.find() method in the MongoDB Kotlin Coroutine 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.
mongoc_collection_t *collection; mongoc_bulk_operation_t *bulk; bson_t *doc; bool r; bson_error_t error; bson_t reply; collection = mongoc_database_get_collection (db, "inventory"); bulk = mongoc_collection_create_bulk_operation_with_opts (collection, NULL); doc = BCON_NEW ( "item", BCON_UTF8 ("journal"), "status", BCON_UTF8 ("A"), "size", "{", "h", BCON_DOUBLE (14), "w", BCON_DOUBLE (21), "uom", BCON_UTF8 ("cm"), "}", "instock", "[", "{", "warehouse", BCON_UTF8 ("A"), "qty", BCON_INT64 (5), "}", "]"); r = mongoc_bulk_operation_insert_with_opts (bulk, doc, NULL, &error); bson_destroy (doc); if (!r) { MONGOC_ERROR ("%s\n", error.message); goto done; } doc = BCON_NEW ( "item", BCON_UTF8 ("notebook"), "status", BCON_UTF8 ("A"), "size", "{", "h", BCON_DOUBLE (8.5), "w", BCON_DOUBLE (11), "uom", BCON_UTF8 ("in"), "}", "instock", "[", "{", "warehouse", BCON_UTF8 ("C"), "qty", BCON_INT64 (5), "}", "]"); r = mongoc_bulk_operation_insert_with_opts (bulk, doc, NULL, &error); bson_destroy (doc); if (!r) { MONGOC_ERROR ("%s\n", error.message); goto done; } doc = BCON_NEW ( "item", BCON_UTF8 ("paper"), "status", BCON_UTF8 ("D"), "size", "{", "h", BCON_DOUBLE (8.5), "w", BCON_DOUBLE (11), "uom", BCON_UTF8 ("in"), "}", "instock", "[", "{", "warehouse", BCON_UTF8 ("A"), "qty", BCON_INT64 (60), "}", "]"); r = mongoc_bulk_operation_insert_with_opts (bulk, doc, NULL, &error); bson_destroy (doc); if (!r) { MONGOC_ERROR ("%s\n", error.message); goto done; } doc = BCON_NEW ( "item", BCON_UTF8 ("planner"), "status", BCON_UTF8 ("D"), "size", "{", "h", BCON_DOUBLE (22.85), "w", BCON_DOUBLE (30), "uom", BCON_UTF8 ("cm"), "}", "instock", "[", "{", "warehouse", BCON_UTF8 ("A"), "qty", BCON_INT64 (40), "}", "]"); r = mongoc_bulk_operation_insert_with_opts (bulk, doc, NULL, &error); bson_destroy (doc); if (!r) { MONGOC_ERROR ("%s\n", error.message); goto done; } doc = BCON_NEW ( "item", BCON_UTF8 ("postcard"), "status", BCON_UTF8 ("A"), "size", "{", "h", BCON_DOUBLE (10), "w", BCON_DOUBLE (15.25), "uom", BCON_UTF8 ("cm"), "}", "instock", "[", "{", "warehouse", BCON_UTF8 ("B"), "qty", BCON_INT64 (15), "}","{", "warehouse", BCON_UTF8 ("C"), "qty", BCON_INT64 (35), "}", "]"); r = mongoc_bulk_operation_insert_with_opts (bulk, doc, NULL, &error); bson_destroy (doc); if (!r) { MONGOC_ERROR ("%s\n", error.message); goto done; } /* "reply" is initialized on success or error */ r = (bool) mongoc_bulk_operation_execute (bulk, &reply, &error); if (!r) { MONGOC_ERROR ("%s\n", error.message); }
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 } ] }") ));
collection.insertMany( listOf( Document("item", "journal") .append("status", "A") .append("size", Document("h", 14).append("w", 21).append("uom", "cm")) .append("instock", listOf( Document("warehouse", "A").append("qty", 5), )), Document("item", "notebook") .append("status", "A") .append("size", Document("h", 8.5).append("w", 11).append("uom", "in")) .append("instock", listOf( Document("warehouse", "C").append("qty", 5), )), Document("item", "paper") .append("status", "D") .append("size", Document("h", 8.5).append("w", 11).append("uom", "in")) .append("instock", listOf( Document("warehouse", "A").append("qty", 60), )), Document("item", "planner") .append("status", "D") .append("size", Document("h", 22.85).append("w", 30).append("uom", "cm")) .append("instock", listOf( Document("warehouse", "A").append("qty", 40), )), Document("item", "postcard") .append("status", "A") .append("size", Document("h", 10).append("w", 15.25).append("uom", "cm")) .append("instock", listOf( Document("warehouse", "B").append("qty", 15), Document("warehouse", "C").append("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()
Return All Fields in Matching Documents
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 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" } )
Copy the following expression into the Filter field:
{ status: "A" } Click Find.
mongoc_collection_t *collection; bson_t *filter; mongoc_cursor_t *cursor; collection = mongoc_database_get_collection (db, "inventory"); filter = BCON_NEW ("status", BCON_UTF8 ("A")); cursor = mongoc_collection_find_with_opts (collection, filter, NULL, NULL);
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"));
val findFlow = 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"
Return the Specified Fields and the _id
Field Only
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 } )
Copy the following expression into the Filter field:
{ status: "A" } Click Options to open the additional query options.
Copy the following expression into the Project field:
{ item: 1, status: 1 } Click Find.
mongoc_collection_t *collection; bson_t *filter; bson_t *opts; mongoc_cursor_t *cursor; collection = mongoc_database_get_collection (db, "inventory"); filter = BCON_NEW ("status", BCON_UTF8 ("A")); opts = BCON_NEW ("projection", "{", "item", BCON_INT64 (1), "status", BCON_INT64 (1), "}"); cursor = mongoc_collection_find_with_opts (collection, filter, opts, NULL);
Be sure to also clean up any open resources by calling the following methods, as appropriate:
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"));
val findFlow = 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"
Suppress _id
Field
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 } )
Copy the following expression into the Filter field:
{ status: "A" } Click Options to open the additional query options.
Copy the following expression into the Project field:
{ item: 1, status: 1, _id: 0 } Click Find.
mongoc_collection_t *collection; bson_t *filter; bson_t *opts; mongoc_cursor_t *cursor; collection = mongoc_database_get_collection (db, "inventory"); filter = BCON_NEW ("status", BCON_UTF8 ("A")); opts = BCON_NEW ("projection", "{", "item", BCON_INT64 (1), "status", BCON_INT64 (1), "_id", BCON_INT64 (0), "}"); cursor = mongoc_collection_find_with_opts (collection, filter, opts, NULL);
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()));
val findFlow = 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.
Return All But the Excluded Fields
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 } )
Copy the following expression into the Filter field:
{ status: "A" } Click Options to open the additional query options.
Copy the following expression into the Project field:
{ status: 0, instock: 0 } Click Find.
mongoc_collection_t *collection; bson_t *filter; bson_t *opts; mongoc_cursor_t *cursor; collection = mongoc_database_get_collection (db, "inventory"); filter = BCON_NEW ("status", BCON_UTF8 ("A")); opts = BCON_NEW ("projection", "{", "status", BCON_INT64 (0), "instock", BCON_INT64 (0), "}"); cursor = mongoc_collection_find_with_opts (collection, filter, opts, NULL);
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"));
val findFlow = 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.
Return Specific Fields in Embedded 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 thesize
document.
The uom
field remains embedded in the size
document.
db.inventory.find( { status: "A" }, { item: 1, status: 1, "size.uom": 1 } )
Copy the following expression into the Filter field:
{ status: "A" } Click Options to open the additional query options.
Copy the following expression into the Project field:
{ item: 1, status: 1, "size.uom": 1 } Click Find.
mongoc_collection_t *collection; bson_t *filter; bson_t *opts; mongoc_cursor_t *cursor; collection = mongoc_database_get_collection (db, "inventory"); filter = BCON_NEW ("status", BCON_UTF8 ("A")); opts = BCON_NEW ("projection", "{", "item", BCON_INT64 (1), "status", BCON_INT64 (1), "size.uom", BCON_INT64 (1), "}"); cursor = mongoc_collection_find_with_opts (collection, filter, opts, NULL);
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"));
val findFlow = 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"))
You can also specify embedded fields using the nested form. For example,
{ item: 1, status: 1, size: { uom: 1 } }
.
Suppress Specific Fields in Embedded Documents
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 } )
Copy the following expression into the Filter field:
{ status: "A" } Click Options to open the additional query options.
Copy the following expression into the Project field:
{ "size.uom": 0 } Click Find.
mongoc_collection_t *collection; bson_t *filter; bson_t *opts; mongoc_cursor_t *cursor; collection = mongoc_database_get_collection (db, "inventory"); filter = BCON_NEW ("status", BCON_UTF8 ("A")); opts = BCON_NEW ("projection", "{", "size.uom", BCON_INT64 (0), "}"); cursor = mongoc_collection_find_with_opts (collection, filter, opts, NULL);
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"));
val findFlow = 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"))
You can also specify embedded fields using the nested form. For example,
{ size: { uom: 0 } }
.
Projection on Embedded Documents in an Array
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 theinstock
array.
db.inventory.find( { status: "A" }, { item: 1, status: 1, "instock.qty": 1 } )
Copy the following expression into the Filter field:
{ status: "A" } Click Options to open the additional query options.
Copy the following expression into the Project field:
{ item: 1, status: 1, "instock.qty": 1 } Click Find.
mongoc_collection_t *collection; bson_t *filter; bson_t *opts; mongoc_cursor_t *cursor; collection = mongoc_database_get_collection (db, "inventory"); filter = BCON_NEW ("status", BCON_UTF8 ("A")); opts = BCON_NEW ("projection", "{", "item", BCON_INT64 (1), "status", BCON_INT64 (1), "instock.qty", BCON_INT64 (1), "}"); cursor = mongoc_collection_find_with_opts (collection, filter, opts, NULL);
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"));
val findFlow = 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"))
Project Specific Array Elements in the Returned Array
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 } } )
Copy the following expression into the Filter field:
{ status: "A" } Click Options to open the additional query options.
Copy the following expression into the Project field:
{ item: 1, status: 1, instock: { $slice: -1 } } Click Find.
mongoc_collection_t *collection; bson_t *filter; bson_t *opts; mongoc_cursor_t *cursor; collection = mongoc_database_get_collection (db, "inventory"); filter = BCON_NEW ("status", BCON_UTF8 ("A")); opts = BCON_NEW ("projection", "{", "item", BCON_INT64 (1), "status", BCON_INT64 (1), "instock", "{", "$slice", BCON_INT64 (-1), "}", "}"); cursor = mongoc_collection_find_with_opts (collection, filter, opts, NULL);
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{ {"$slice", -1}, }}, } cursor, err := coll.Find( context.TODO(), bson.D{ {"status", "A"}, }, options.Find().SetProjection(projection), )
findPublisher = collection.find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)));
To specify a projection document, chain the
com.mongodb.client.FindIterable.projection method to the
find
method. The example uses the
com.mongodb.client.model.Projections class to create the
projection documents.
findIterable = collection.find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)));
To specify a projection document, chain the
FindFlow.projection() method to the
find()
method. The example uses the
com.mongodb.client.model.Projections class to create the
projection documents.
val findFlow = collection .find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)))
cursor = db.inventory.find( {"status": "A"}, {"item": 1, "status": 1, "instock": {"$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 operators that you can use 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 does 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 } } )
Copy the following expression into the Filter field:
{ status: "A" } Click Options to open the additional query options.
Copy the following expression into the Project field:
{ item: 1, status: 1, instock: { $slice: -1 } } Click Find.
mongoc_collection_t *collection; bson_t *filter; bson_t *opts; mongoc_cursor_t *cursor; collection = mongoc_database_get_collection (db, "inventory"); filter = BCON_NEW ("status", BCON_UTF8 ("A")); opts = BCON_NEW ("projection", "{", "item", BCON_INT64 (1), "status", BCON_INT64 (1), "instock", "{", "$slice", BCON_INT64 (-1), "}", "}"); cursor = mongoc_collection_find_with_opts (collection, filter, opts, NULL);
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{ {"$slice", -1}, }}, } cursor, err := coll.Find( context.TODO(), bson.D{ {"status", "A"}, }, options.Find().SetProjection(projection), )
findPublisher = collection.find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)));
To specify a projection document, chain the
com.mongodb.client.FindIterable.projection method to the
find
method. The example uses the
com.mongodb.client.model.Projections class to create the
projection documents.
findIterable = collection.find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)));
To specify a projection document, chain the
FindFlow.projection() method to the
find()
method. The example uses the
com.mongodb.client.model.Projections class to create the
projection documents.
val findFlow = collection .find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)))
cursor = db.inventory.find( {"status": "A"}, {"item": 1, "status": 1, "instock": {"$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 } } )
Copy the following expression into the Filter field:
{ status: "A" } Click Options to open the additional query options.
Copy the following expression into the Project field:
{ item: 1, status: 1, instock: { $slice: -1 } } Click Find.
mongoc_collection_t *collection; bson_t *filter; bson_t *opts; mongoc_cursor_t *cursor; collection = mongoc_database_get_collection (db, "inventory"); filter = BCON_NEW ("status", BCON_UTF8 ("A")); opts = BCON_NEW ("projection", "{", "item", BCON_INT64 (1), "status", BCON_INT64 (1), "instock", "{", "$slice", BCON_INT64 (-1), "}", "}"); cursor = mongoc_collection_find_with_opts (collection, filter, opts, NULL);
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{ {"$slice", -1}, }}, } cursor, err := coll.Find( context.TODO(), bson.D{ {"status", "A"}, }, options.Find().SetProjection(projection), )
findPublisher = collection.find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)));
To specify a projection document, chain the
com.mongodb.client.FindIterable.projection method to the
find
method. The example uses the
com.mongodb.client.model.Projections class to create the
projection documents.
findIterable = collection.find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)));
To specify a projection document, chain the
FindFlow.projection() method to the
find()
method. The example uses the
com.mongodb.client.model.Projections class to create the
projection documents.
val findFlow = collection .find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)))
cursor = db.inventory.find( {"status": "A"}, {"item": 1, "status": 1, "instock": {"$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 operators that you can use 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 } } )
Copy the following expression into the Filter field:
{ status: "A" } Click Options to open the additional query options.
Copy the following expression into the Project field:
{ item: 1, status: 1, instock: { $slice: -1 } } Click Find.
mongoc_collection_t *collection; bson_t *filter; bson_t *opts; mongoc_cursor_t *cursor; collection = mongoc_database_get_collection (db, "inventory"); filter = BCON_NEW ("status", BCON_UTF8 ("A")); opts = BCON_NEW ("projection", "{", "item", BCON_INT64 (1), "status", BCON_INT64 (1), "instock", "{", "$slice", BCON_INT64 (-1), "}", "}"); cursor = mongoc_collection_find_with_opts (collection, filter, opts, NULL);
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{ {"$slice", -1}, }}, } cursor, err := coll.Find( context.TODO(), bson.D{ {"status", "A"}, }, options.Find().SetProjection(projection), )
findPublisher = collection.find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)));
To specify a projection document, chain the
com.mongodb.client.FindIterable.projection method to the
find
method. The example uses the
com.mongodb.client.model.Projections class to create the
projection documents.
findIterable = collection.find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)));
To specify a projection document, chain the
FindFlow.projection() method to the
find()
method. The example uses the
com.mongodb.client.model.Projections class to create the
projection documents.
val findFlow = collection .find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)))
cursor = db.inventory.find( {"status": "A"}, {"item": 1, "status": 1, "instock": {"$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 operators that you can use 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 does 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 } } )
Copy the following expression into the Filter field:
{ status: "A" } Click Options to open the additional query options.
Copy the following expression into the Project field:
{ item: 1, status: 1, instock: { $slice: -1 } } Click Find.
mongoc_collection_t *collection; bson_t *filter; bson_t *opts; mongoc_cursor_t *cursor; collection = mongoc_database_get_collection (db, "inventory"); filter = BCON_NEW ("status", BCON_UTF8 ("A")); opts = BCON_NEW ("projection", "{", "item", BCON_INT64 (1), "status", BCON_INT64 (1), "instock", "{", "$slice", BCON_INT64 (-1), "}", "}"); cursor = mongoc_collection_find_with_opts (collection, filter, opts, NULL);
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{ {"$slice", -1}, }}, } cursor, err := coll.Find( context.TODO(), bson.D{ {"status", "A"}, }, options.Find().SetProjection(projection), )
findPublisher = collection.find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)));
To specify a projection document, chain the
com.mongodb.client.FindIterable.projection method to the
find
method. The example uses the
com.mongodb.client.model.Projections class to create the
projection documents.
findIterable = collection.find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)));
To specify a projection document, chain the
FindFlow.projection() method to the
find()
method. The example uses the
com.mongodb.client.model.Projections class to create the
projection documents.
val findFlow = collection .find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)))
cursor = db.inventory.find( {"status": "A"}, {"item": 1, "status": 1, "instock": {"$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 operators that you can use 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 does 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 } } )
Copy the following expression into the Filter field:
{ status: "A" } Click Options to open the additional query options.
Copy the following expression into the Project field:
{ item: 1, status: 1, instock: { $slice: -1 } } Click Find.
mongoc_collection_t *collection; bson_t *filter; bson_t *opts; mongoc_cursor_t *cursor; collection = mongoc_database_get_collection (db, "inventory"); filter = BCON_NEW ("status", BCON_UTF8 ("A")); opts = BCON_NEW ("projection", "{", "item", BCON_INT64 (1), "status", BCON_INT64 (1), "instock", "{", "$slice", BCON_INT64 (-1), "}", "}"); cursor = mongoc_collection_find_with_opts (collection, filter, opts, NULL);
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{ {"$slice", -1}, }}, } cursor, err := coll.Find( context.TODO(), bson.D{ {"status", "A"}, }, options.Find().SetProjection(projection), )
findPublisher = collection.find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)));
To specify a projection document, chain the
com.mongodb.client.FindIterable.projection method to the
find
method. The example uses the
com.mongodb.client.model.Projections class to create the
projection documents.
findIterable = collection.find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)));
To specify a projection document, chain the
FindFlow.projection() method to the
find()
method. The example uses the
com.mongodb.client.model.Projections class to create the
projection documents.
val findFlow = collection .find(eq("status", "A")) .projection(fields(include("item", "status"), slice("instock", -1)))
cursor = db.inventory.find( {"status": "A"}, {"item": 1, "status": 1, "instock": {"$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}} )