mongoc_collection_update_one(3)

1MONGOC_COLLECTION_UPDATE_ONE(3)MongoDB C DriverMONGOC_COLLECTION_UPDATE_ONE(3)
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NAME

6       mongoc_collection_update_one - mongoc_collection_update_one()
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SYNOPSIS

9          bool
10          mongoc_collection_update_one (mongoc_collection_t *collection,
11                                        const bson_t *selector,
12                                        const bson_t *update,
13                                        const bson_t *opts,
14                                        bson_t *reply,
15                                        bson_error_t *error);
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PARAMETERS

18       · collection: A mongoc_collection_t.
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20       · selector:  A  bson_t  containing  the query to match the document for
21         updating.
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23       · update: A bson_t containing the update to perform.
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25       · reply: Optional. An uninitialized bson_t populated  with  the  update
26         result, or NULL.
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28       · error: An optional location for a bson_error_t or NULL.
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30       opts may be NULL or a BSON document with additional command options:
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32       · writeConcern:   Construct   a  mongoc_write_concern_t  and  use  mon‐
33         goc_write_concern_append to add the write concern to  opts.  See  the
34         example code for mongoc_client_write_command_with_opts.
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36       · sessionId:  First,  construct  a  mongoc_client_session_t  with  mon‐
37         goc_client_start_session. You  can  begin  a  transaction  with  mon‐
38         goc_client_session_start_transaction, optionally with a mongoc_trans‐
39         action_opt_t that overrides the options  inherited  from  collection,
40         and  use mongoc_client_session_append to add the session to opts. See
41         the example code for mongoc_client_session_t.
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43       · validate:    Construct    a     bitwise-or     of     all     desired
44         bson_validate_flags_t. Set to false to skip client-side validation of
45         the provided BSON documents.
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47       · bypassDocumentValidation: Set to true to skip server-side schema val‐
48         idation of the provided BSON documents.
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50       · collation:  Configure  textual  comparisons.  See  Setting  Collation
51         Order, and the MongoDB Manual entry on Collation. Collation  requires
52         MongoDB 3.2 or later, otherwise an error is returned.
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54       · upsert:  When true, creates a new document if no document matches the
55         query.
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57       · arrayFilters: An array of filters specifying to which array  elements
58         an update should apply.
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DESCRIPTION

61       This  function  updates at most one document in collection that matches
62       selector.
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64       To update multiple documents see mongoc_collection_update_many.
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66       If you pass a non-NULL reply, it is filled out  with  fields   matched‐
67       Count, modifiedCount, and optionally upsertedId if applicable. If there
68       is a server error then reply contains either a "writeErrors" array with
69       one  subdocument  or  a  "writeConcernErrors"  array. The reply must be
70       freed with bson_destroy().
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ERRORS

81       Errors are propagated via the error parameter.
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RETURNS

84       Returns  true  if successful. Returns false and sets error if there are
85       invalid arguments or a server or network error.
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87       A write concern timeout or write concern error is considered a failure.
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EXAMPLE

90       example-update.c.INDENT 0.0
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92          #include "mongoc/mongoc.h"
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94          int
95          main (int argc, char **argv)
96          {
97             bson_t *to_insert = BCON_NEW ("_id", BCON_INT32 (1));
98             bson_t *selector = BCON_NEW ("_id", "{", "$gt", BCON_INT32 (0), "}");
99             bson_t *update = BCON_NEW ("$set", "{", "x", BCON_INT32 (1), "}");
100             const bson_t *next_doc;
101             char *to_str;
102             bson_error_t error = {0};
103             mongoc_cursor_t *cursor;
104             mongoc_client_t *client;
105             mongoc_collection_t *coll;
106             const char *uri_string = "mongodb://localhost:27017/?appname=example-update";
107             mongoc_uri_t *uri = mongoc_uri_new_with_error (uri_string, &error);
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109             if (!uri) {
110                fprintf (stderr,
111                         "failed to parse URI: %s\n"
112                         "error message:       %s\n",
113                         uri_string,
114                         error.message);
115                return EXIT_FAILURE;
116             }
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118             client = mongoc_client_new_from_uri (uri);
119             if (!client) {
120                return EXIT_FAILURE;
121             }
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123             coll = mongoc_client_get_collection (client, "db", "example_coll");
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125             mongoc_client_set_error_api (client, 2);
126             /* insert a document */
127             if (!mongoc_collection_insert_one (coll, to_insert, NULL, NULL, &error)) {
128                fprintf (stderr, "insert failed: %s\n", error.message);
129                return EXIT_FAILURE;
130             }
131
132             if (!mongoc_collection_update_one (
133                    coll, selector, update, NULL, NULL, &error)) {
134                fprintf (stderr, "update failed: %s\n", error.message);
135                return EXIT_FAILURE;
136             }
137
138             to_str = bson_as_relaxed_extended_json (to_insert, NULL);
139             printf ("inserted: %s\n", to_str);
140             bson_free (to_str);
141
142             cursor = mongoc_collection_find_with_opts (coll, selector, NULL, NULL);
143             BSON_ASSERT (mongoc_cursor_next (cursor, &next_doc));
144             printf ("after update, collection has the following document:\n");
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146             to_str = bson_as_relaxed_extended_json (next_doc, NULL);
147             printf ("%s\n", to_str);
148             bson_free (to_str);
149
150             BSON_ASSERT (mongoc_collection_drop (coll, NULL));
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152             bson_destroy (to_insert);
153             bson_destroy (update);
154             bson_destroy (selector);
155             mongoc_collection_destroy (coll);
156             mongoc_uri_destroy (uri);
157             mongoc_client_destroy (client);
158
159             return EXIT_SUCCESS;
160          }
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AUTHOR

164       MongoDB, Inc
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COPYRIGHT

167       2017-present, MongoDB, Inc
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1721.14.0                           Feb 22, 2019  MONGOC_COLLECTION_UPDATE_ONE(3)