1MONGOC_COLLECTION_COUNT_WITH_OPTMSo(n3g)oDB C DrMiOvNeGrOC_COLLECTION_COUNT_WITH_OPTS(3)
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3
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NAME

6       mongoc_collection_count_with_opts - mongoc_collection_count_with_opts()
7

DEPRECATED

9       This  function  is  deprecated and should not be used in new code.  Use
10       mongoc_collection_count_documents or  mongoc_collection_estimated_docu‐
11       ment_count instead.
12
13       mongoc_collection_count_documents  has  similar  performance to calling
14       mongoc_collection_count with a non-NULL query,  and  is  guaranteed  to
15       retrieve  an  accurate  collection count. See migrating from deprecated
16       count functions for details.
17
18       mongoc_collection_estimated_document_count has the same performance  as
19       calling  mongoc_collection_count  with a NULL query, but is not guaran‐
20       teed to retrieve an accurate collection count.
21

SYNOPSIS

23          int64_t
24          mongoc_collection_count_with_opts (mongoc_collection_t *collection,
25                                             mongoc_query_flags_t flags,
26                                             const bson_t *query,
27                                             int64_t skip,
28                                             int64_t limit,
29                                             const bson_t *opts,
30                                             const mongoc_read_prefs_t *read_prefs,
31                                             bson_error_t *error)
32           BSON_GNUC_DEPRECATED_FOR (mongoc_collection_count_documents or
33                                     mongoc_collection_estimated_document_count);
34

PARAMETERS

36       · collection: A mongoc_collection_t.
37
38       · flags: A mongoc_query_flags_t.
39
40       · query: A bson_t containing the query.
41
42       · skip: A int64_t, zero to ignore.
43
44       · limit: A int64_t, zero to ignore.
45
46       · opts: A bson_t, NULL to ignore.
47
48       · read_prefs: An optional mongoc_read_prefs_t, otherwise uses the  col‐
49         lection's read preference.
50
51       · error: An optional location for a bson_error_t or NULL.
52
53       opts may be NULL or a BSON document with additional command options:
54
55       · readConcern:   Construct   a   mongoc_read_concern_t   and  use  mon‐
56         goc_read_concern_append to add the read  concern  to  opts.  See  the
57         example  code  for mongoc_client_read_command_with_opts. Read concern
58         requires MongoDB 3.2 or later, otherwise an error is returned.
59
60       · sessionId:  First,  construct  a  mongoc_client_session_t  with  mon‐
61         goc_client_start_session.  You  can  begin  a  transaction  with mon‐
62         goc_client_session_start_transaction, optionally with a mongoc_trans‐
63         action_opt_t  that  overrides  the options inherited from collection,
64         and use mongoc_client_session_append to add the session to opts.  See
65         the example code for mongoc_client_session_t.
66
67       · collation:  Configure  textual  comparisons.  See  Setting  Collation
68         Order, and the MongoDB Manual entry on Collation. Collation  requires
69         MongoDB 3.2 or later, otherwise an error is returned.
70
71       · serverId:  To  target  a specific server, include an int32 "serverId"
72         field. Obtain the id  by  calling  mongoc_client_select_server,  then
73         mongoc_server_description_id on its return value.
74

DESCRIPTION

76       This  function  shall  execute a count query on the underlying 'collec‐
77       tion'. The bson 'query' is not validated, simply passed along as appro‐
78       priate to the server.  As such, compatibility and errors should be val‐
79       idated in the appropriate server documentation.
80
81       The mongoc_read_concern_t specified on the mongoc_collection_t will  be
82       used,  if any. If read_prefs is NULL, the collection's read preferences
83       are used.
84
85       In addition to the standard functionality available from mongoc_collec‐
86       tion_count,  this  function allows the user to add arbitrary extra keys
87       to the count.  This pass through enables features such as  hinting  for
88       counts.
89
90       For more information, see the query reference at the MongoDB website.
91
92       This  function  is considered a retryable read operation.  Upon a tran‐
93       sient error (a network error, errors due to replica set failover, etc.)
94       the  operation  is  safely retried once.  If retryreads is false in the
95       URI (see mongoc_uri_t) the retry behavior does not apply.
96

ERRORS

98       Errors are propagated via the error parameter.
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RETURNS

101       -1 on failure, otherwise the number of documents counted.
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EXAMPLES

104       Basic Counting.INDENT 0.0
105
106          #include <bson/bson.h>
107          #include <mongoc/mongoc.h>
108          #include <stdio.h>
109
110          static void
111          print_query_count (mongoc_collection_t *collection, bson_t *query)
112          {
113             bson_error_t error;
114             int64_t count;
115             bson_t opts;
116
117             bson_init (&opts);
118             BSON_APPEND_UTF8 (&opts, "hint", "_id_");
119
120             count = mongoc_collection_count_with_opts (
121                collection, MONGOC_QUERY_NONE, query, 0, 0, &opts, NULL, &error);
122
123             bson_destroy (&opts);
124
125             if (count < 0) {
126                fprintf (stderr, "Count failed: %s\n", error.message);
127             } else {
128                printf ("%" PRId64 " documents counted.\n", count);
129             }
130          }
131Counting with Collation.INDENT 0.0
132
133          #include <bson/bson.h>
134          #include <mongoc/mongoc.h>
135          #include <stdio.h>
136
137          static void
138          print_query_count (mongoc_collection_t *collection, bson_t *query)
139          {
140             bson_t *selector;
141             bson_t *opts;
142             bson_error_t error;
143             int64_t count;
144
145             selector = BCON_NEW ("_id", "{", "$gt", BCON_UTF8 ("one"), "}");
146
147             /* "One" normally sorts before "one"; make "one" come first */
148             opts = BCON_NEW ("collation",
149                              "{",
150                              "locale",
151                              BCON_UTF8 ("en_US"),
152                              "caseFirst",
153                              BCON_UTF8 ("lower"),
154                              "}");
155
156             count = mongoc_collection_count_with_opts (
157                collection, MONGOC_QUERY_NONE, query, 0, 0, opts, NULL, &error);
158
159             bson_destroy (selector);
160             bson_destroy (opts);
161
162             if (count < 0) {
163                fprintf (stderr, "Count failed: %s\n", error.message);
164             } else {
165                printf ("%" PRId64 " documents counted.\n", count);
166             }
167          }
168

AUTHOR

170       MongoDB, Inc
171
173       2017-present, MongoDB, Inc
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1781.15.2                           Nov 06, 20M1O9NGOC_COLLECTION_COUNT_WITH_OPTS(3)
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