MongoCollection.findOne - multiple declarations
Function MongoCollection.findOne
Function MongoCollection.findOne
Queries the collection for existing documents.
auto findOne(R, T, U)
(
T query,
U projection,
FindOptions options = FindOptions .init
)
if (!is(U == FindOptions));
Returns
By default, a Bson value of the matching document is returned, or Bson(null)
when no document matched. For types R that are not Bson, the returned value is either
of type R
, or of type , if R
is not a reference/pointer type.
The projection parameter limits what fields are returned by the database, see projection documentation linked below.
Throws
Exception if a DB communication error or a query error occurred.
See Also
- Querying: http://www.mongodb.org/display/DOCS/Querying - Projection: https://www.mongodb.com/docs/manual/tutorial/project-fields-from-query-results/#std-label-projections - find
Example
import vibe .db .mongo .mongo;
void test()
{
auto coll = connectMongoDB("127.0.0.1") .getCollection("test");
// find documents with status == "A"
auto x = coll .findOne(["status": "A"], ["status": true, "otherField": true]);
// x now only contains _id (implicit, unless you make it `false`), status and otherField
}
Function MongoCollection.findOne
Queries the collection for existing documents.
Returns
By default, a Bson value of the matching document is returned, or Bson(null)
when no document matched. For types R that are not Bson, the returned value is either
of type R
, or of type , if R
is not a reference/pointer type.
Throws
Exception if a DB communication error or a query error occurred.