NAME

       mongoc_collection_count_with_opts - mongoc_collection_count_with_opts()

DEPRECATED

       This   function   is   deprecated   and   should   not   be   used   in   new  code.   Use
       mongoc_collection_count_documents()    or     mongoc_collection_estimated_document_count()
       instead.

       mongoc_collection_count_documents()     has     similar     performance     to     calling
       mongoc_collection_count() with a non-NULL query, and is guaranteed to retrieve an accurate
       collection count. See migrating from deprecated count functions for details.

       mongoc_collection_estimated_document_count()   has   the   same   performance  as  calling
       mongoc_collection_count() with a NULL query, but is not guaranteed to retrieve an accurate
       collection count.

SYNOPSIS

          int64_t
          mongoc_collection_count_with_opts (mongoc_collection_t *collection,
                                             mongoc_query_flags_t flags,
                                             const bson_t *query,
                                             int64_t skip,
                                             int64_t limit,
                                             const bson_t *opts,
                                             const mongoc_read_prefs_t *read_prefs,
                                             bson_error_t *error)
           BSON_GNUC_DEPRECATED_FOR (mongoc_collection_count_documents or
                                     mongoc_collection_estimated_document_count);

PARAMETERS

       • collection: A mongoc_collection_t.

       • flags: A mongoc_query_flags_t.

       • query: A bson_t containing the query.

       • skip: A int64_t, zero to ignore.

       • limit: A int64_t, zero to ignore.

       • opts: A bson_t, NULL to ignore.

       • read_prefs:  An  optional  mongoc_read_prefs_t,  otherwise  uses  the  collection's read
         preference.

       • error: An optional location for a bson_error_t or NULL.

       opts may be NULL or a BSON document with additional command options:

       • readConcern: Construct a mongoc_read_concern_t and use  mongoc_read_concern_append()  to
         add     the     read     concern     to    opts.    See    the    example    code    for
         mongoc_client_read_command_with_opts(). Read concern  requires  MongoDB  3.2  or  later,
         otherwise an error is returned.

       • sessionId:       First,       construct       a       mongoc_client_session_t       with
         mongoc_client_start_session().     You     can     begin     a     transaction      with
         mongoc_client_session_start_transaction(),  optionally  with  a mongoc_transaction_opt_t
         that    overrides    the    options    inherited    from     collection,     and     use
         mongoc_client_session_append()  to  add  the  session  to opts. See the example code for
         mongoc_client_session_t.

       • collation: Configure textual comparisons. See Setting Collation Order, and  the  MongoDB
         Manual  entry  on Collation. Collation requires MongoDB 3.2 or later, otherwise an error
         is returned.

       • serverId: To target a specific server, include an int32 "serverId" field. Obtain the  id
         by  calling  mongoc_client_select_server(),  then  mongoc_server_description_id() on its
         return value.

DESCRIPTION

       This function shall execute a count query on the underlying 'collection'. The bson 'query'
       is   not  validated,  simply  passed  along  as  appropriate  to  the  server.   As  such,
       compatibility and errors should be validated in the appropriate server documentation.

       The mongoc_read_concern_t specified on the mongoc_collection_t will be used,  if  any.  If
       read_prefs is NULL, the collection's read preferences are used.

       In  addition  to  the  standard functionality available from mongoc_collection_count, this
       function allows the user to add arbitrary extra keys to  the  count.   This  pass  through
       enables features such as hinting for counts.

       For more information, see the query reference at the MongoDB website.

       This function is considered a retryable read operation.  Upon a transient error (a network
       error, errors due to replica set failover, etc.) the operation is safely retried once.  If
       retryreads is false in the URI (see mongoc_uri_t) the retry behavior does not apply.

ERRORS

       Errors are propagated via the error parameter.

RETURNS

       -1 on failure, otherwise the number of documents counted.

EXAMPLES

       Basic Counting

          #include <bson/bson.h>
          #include <mongoc/mongoc.h>
          #include <stdio.h>

          static void
          print_query_count (mongoc_collection_t *collection, bson_t *query)
          {
             bson_error_t error;
             int64_t count;
             bson_t opts;

             bson_init (&opts);
             BSON_APPEND_UTF8 (&opts, "hint", "_id_");

             count = mongoc_collection_count_with_opts (
                collection, MONGOC_QUERY_NONE, query, 0, 0, &opts, NULL, &error);

             bson_destroy (&opts);

             if (count < 0) {
                fprintf (stderr, "Count failed: %s\n", error.message);
             } else {
                printf ("%" PRId64 " documents counted.\n", count);
             }
          }

       Counting with Collation

          #include <bson/bson.h>
          #include <mongoc/mongoc.h>
          #include <stdio.h>

          static void
          print_query_count (mongoc_collection_t *collection, bson_t *query)
          {
             bson_t *selector;
             bson_t *opts;
             bson_error_t error;
             int64_t count;

             selector = BCON_NEW ("_id", "{", "$gt", BCON_UTF8 ("one"), "}");

             /* "One" normally sorts before "one"; make "one" come first */
             opts = BCON_NEW ("collation",
                              "{",
                              "locale",
                              BCON_UTF8 ("en_US"),
                              "caseFirst",
                              BCON_UTF8 ("lower"),
                              "}");

             count = mongoc_collection_count_with_opts (
                collection, MONGOC_QUERY_NONE, query, 0, 0, opts, NULL, &error);

             bson_destroy (selector);
             bson_destroy (opts);

             if (count < 0) {
                fprintf (stderr, "Count failed: %s\n", error.message);
             } else {
                printf ("%" PRId64 " documents counted.\n", count);
             }
          }

AUTHOR

       MongoDB, Inc

COPYRIGHT

       2017-present, MongoDB, Inc