Mongoc_collection_find_and_modify (3) Linux Manual Page

mongoc_collection_find_and_modify() – Update and return an object.

Synopsis

bool
mongoc_collection_find_and_modify (mongoc_collection_t *collection,
 const bson_t *query,
 const bson_t *sort,
 const bson_t *update,
 const bson_t *fields,
 bool _remove,
 bool upsert,
 bool _new,
 bson_t *reply,
 bson_error_t *error);

Parameters

collection: A mongoc_collection_t \&.

query: A bson_t containing the query to locate target document(s).

sort: A bson_t containing the sort order for query \&.

update: A bson_t containing an update spec.

fields: An optional bson_t containing the fields to return or NULL \&.

_remove: If the matching documents should be removed.

upsert: If an upsert should be performed.

_new: If the new version of the document should be returned.

reply: An optional location for a bson_t that will be initialized with the result or NULL \&.

error: An optional location for a bson_error_t or NULL \&.

Description

Update and return an object.

This is a thin wrapper around the findAndModify command. Either update or _remove arguments are required.

NOTE

As of MongoDB 3.2 and mongoc 1.3.0, the mongoc_write_concern_t specified on the mongoc_collection_t will be used, if any.

Errors

Errors are propagated via the error parameter.

Returns

Returns either the document before or after modification based on the _new parameter.

Example

#include <bcon.h>
#include <mongoc.h>
#include <stdio.h>
int
main (int argc,
 char *argv[])
{
 mongoc_collection_t *collection;
 mongoc_client_t *client;
 bson_error_t error;
 bson_t *query;
 bson_t *update;
 bson_t reply;
 char *str;
 mongoc_init ();
 client = mongoc_client_new ("mongodb://127.0.0.1:27017/");
 collection = mongoc_client_get_collection (client, "test", "test");
 /*
 * Build our query, {"cmpxchg": 1}
 */
 query = BCON_NEW ("cmpxchg", BCON_INT32 (1));
 /*
 * Build our update. {"$set": {"cmpxchg": 2}}
 */
 update = BCON_NEW ("$set", "{", "cmpxchg", BCON_INT32 (2), "}");
 /*
 * Submit the findAndModify.
 */
 if (!mongoc_collection_find_and_modify (collection, query, NULL, update, NULL, false, false, true, &reply, &error)) {
 fprintf (stderr, "find_and_modify() failure: %s
", error.message);
 return 1;
 }
 /*
 * Print the result as JSON.
 */
 str = bson_as_json (&reply, NULL);
 printf ("%s
", str);
 bson_free (str);
 /*
 * Cleanup.
 */
 bson_destroy (query);
 bson_destroy (update);
 bson_destroy (&reply);
 mongoc_collection_destroy (collection);
 mongoc_client_destroy (client);
 mongoc_cleanup ();
 return 0;
}

Colophon

This page is part of MongoDB C Driver. Please report any bugs at https://jira.mongodb.org/browse/CDRIVER.

mongoc_collection_find_and_modify (3) Linux Manual Page