Provided by: libmongoc-doc_1.21.0-1build1_all
NAME
mongoc_collection_find_and_modify - mongoc_collection_find_and_modify()
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: Optional pointer to an uninitialized bson_t that will be initialized with the result. • 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. As of MongoDB 3.2, the mongoc_write_concern_t specified on the mongoc_collection_t will be used, if any. reply is always initialized, and must be freed with bson_destroy().
ERRORS
Errors are propagated via the error parameter.
RETURNS
Returns either the document before or after modification based on the _new parameter. A write concern timeout or write concern error is considered a failure. SEE ALSO: mongoc_collection_find_and_modify_with_opts.
EXAMPLE
find-and-modify.c #include <mongoc/mongoc.h> #include <stdio.h> int main (int argc, char *argv[]) { mongoc_collection_t *collection; mongoc_client_t *client; const char *uri_string = "mongodb://127.0.0.1:27017/?appname=find-and-modify-example"; mongoc_uri_t *uri; bson_error_t error; bson_t *query; bson_t *update; bson_t reply; char *str; mongoc_init (); uri = mongoc_uri_new_with_error (uri_string, &error); if (!uri) { fprintf (stderr, "failed to parse URI: %s\n" "error message: %s\n", uri_string, error.message); return EXIT_FAILURE; } client = mongoc_client_new_from_uri (uri); if (!client) { return EXIT_FAILURE; } mongoc_client_set_error_api (client, 2); 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\n", error.message); return EXIT_FAILURE; } /* * Print the result as JSON. */ str = bson_as_canonical_extended_json (&reply, NULL); printf ("%s\n", str); bson_free (str); /* * Cleanup. */ bson_destroy (query); bson_destroy (update); bson_destroy (&reply); mongoc_collection_destroy (collection); mongoc_uri_destroy (uri); mongoc_client_destroy (client); mongoc_cleanup (); return EXIT_SUCCESS; }
AUTHOR
MongoDB, Inc
COPYRIGHT
2017-present, MongoDB, Inc