NAME

       mongoc_session_opts_set_causal_consistency - mongoc_session_opts_set_causal_consistency()

SYNOPSIS

          void
          mongoc_session_opts_set_causal_consistency (mongoc_session_opt_t *opts,
                                                      bool causal_consistency);

       Configure  causal  consistency in a session. If true (the default), each operation in the session will be
       causally ordered after the previous read or write operation. Set to false to disable causal  consistency.
       See the MongoDB Manual Entry for Causal Consistency.

       Unacknowledged   writes   are  not  causally  consistent.  If  you  execute  a  write  operation  with  a
       mongoc_write_concern_t on which you have called mongoc_write_concern_set_w with a value of 0,  the  write
       does not participate in causal consistency.

PARAMETERS

       • opts: A mongoc_session_opt_t.

       • causal_consistency: True or false.

EXAMPLE

          mongoc_client_t *client;
          mongoc_session_opt_t *session_opts;
          mongoc_client_session_t *client_session;
          mongoc_collection_t *collection;
          bson_t insert_opts = BSON_INITIALIZER;
          bson_t *doc;
          bson_error_t error;
          bool r;

          client = mongoc_client_new ("mongodb://example/?appname=session-opts-example");
          mongoc_client_set_error_api (client, 2);

          session_opts = mongoc_session_opts_new ();
          mongoc_session_opts_set_causal_consistency (session_opts, false);
          client_session = mongoc_client_start_session (client, session_opts, &error);
          mongoc_session_opts_destroy (session_opts);

          if (!client_session) {
             fprintf (stderr, "Failed to start session: %s\n", error.message);
             abort ();
          }

          collection = mongoc_client_get_collection (client, "test", "collection");
          doc = BCON_NEW ("_id", BCON_INT32 (1));
          r = mongoc_client_session_append (client_session, &insert_opts, NULL);
          if (!r) {
             fprintf (stderr, "mongoc_client_session_append failed: %s\n", error.message);
             abort ();
          }

          r = mongoc_collection_insert_one (
             collection, doc, &insert_opts, NULL /* reply */, &error);

          if (!r) {
             fprintf (stderr, "Insert failed: %s\n", error.message);
             abort ();
          }

AUTHOR

       MongoDB, Inc

COPYRIGHT

       2017-present, MongoDB, Inc

1.16.1                                            Mar 03, 2020     MONGOC_SESSION_OPTS_SET_CAUSAL_CONSISTENCY(3)