1MONGOC_DATABASE_READ_COMMAND_WITH_OPlTiSbM(mO3oN)nGgOoCc_DATABASE_READ_COMMAND_WITH_OPTS(3)
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NAME

6       mongoc_database_read_command_with_opts    -   mongoc_database_read_com‐
7       mand_with_opts()
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SYNOPSIS

10          bool
11          mongoc_database_read_command_with_opts (mongoc_database_t *database,
12                                                  const bson_t *command,
13                                                  const mongoc_read_prefs_t *read_prefs,
14                                                  const bson_t *opts,
15                                                  bson_t *reply,
16                                                  bson_error_t *error);
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18       Execute a command on the server, applying logic  that  is  specific  to
19       commands that read, and taking the MongoDB server version into account.
20       To send a raw command to the server without any of this logic, use mon‐
21       goc_database_command_simple.
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23       Use this function for commands that read such as "count" or "distinct".
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25       Read preferences, read concern, and collation can be overridden by var‐
26       ious sources. In a transaction, read concern and write concern are pro‐
27       hibited  in  opts  and the read preference must be primary or NULL. The
28       highest-priority sources for these options are listed first in the fol‐
29       lowing table. No write concern is applied.
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31                    ┌─────────────────┬──────────────┬───────────┐
32                    │Read Preferences │ Read Concern │ Collation │
33                    ├─────────────────┼──────────────┼───────────┤
34                    │read_prefs       │ opts         │ opts      │
35                    ├─────────────────┼──────────────┼───────────┤
36                    │Transaction      │ Transaction  │           │
37                    ├─────────────────┼──────────────┼───────────┤
38                    │database         │              │           │
39                    └─────────────────┴──────────────┴───────────┘
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41       See  the  example  for transactions and for the "distinct" command with
42       opts.
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44       reply is always initialized, and must be freed with bson_destroy().
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46       This function is considered a retryable read operation.  Upon  a  tran‐
47       sient error (a network error, errors due to replica set failover, etc.)
48       the operation is safely retried once.  If retryreads is  false  in  the
49       URI (see mongoc_uri_t) the retry behavior does not apply.
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51       Retry  logic  occurs  regardless  of  the  underlying command. Retrying
52       mapReduce has the potential for degraded performance.  Retrying a  get‐
53       More command has the potential to miss results. For those commands, use
54       generic command helpers  (like  mongoc_database_command_with_opts)  in‐
55       stead.
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PARAMETERS

58       • database: A mongoc_database_t.
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60       • command: A bson_t containing the command specification.
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62       • read_prefs: An optional mongoc_read_prefs_t.
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64       • opts: A bson_t containing additional options.
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66       • reply: A location for the resulting document.
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68       • error: An optional location for a bson_error_t or NULL.
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70       opts may be NULL or a BSON document with additional command options:
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72       • readConcern:   Construct   a   mongoc_read_concern_t   and  use  mon‐
73         goc_read_concern_append to add the read concern to opts. See the  ex‐
74         ample code for mongoc_client_read_command_with_opts. Read concern re‐
75         quires MongoDB 3.2 or later, otherwise an error is returned.
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77       • sessionId:  First,  construct  a  mongoc_client_session_t  with  mon‐
78         goc_client_start_session.  You  can  begin  a  transaction  with mon‐
79         goc_client_session_start_transaction, optionally with a mongoc_trans‐
80         action_opt_t  that overrides the options inherited from database, and
81         use mongoc_client_session_append to add the session to opts. See  the
82         example code for mongoc_client_session_t.
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84       • collation:  Configure  textual comparisons. See Setting Collation Or‐
85         der, and the MongoDB Manual entry on  Collation.  Collation  requires
86         MongoDB 3.2 or later, otherwise an error is returned.
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88       • serverId:  To  target  a specific server, include an int32 "serverId"
89         field. Obtain the id  by  calling  mongoc_client_select_server,  then
90         mongoc_server_description_id on its return value.
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92       Consult  the  MongoDB  Manual  entry on Database Commands for each com‐
93       mand's arguments.
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ERRORS

96       Errors are propagated via the error parameter.
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RETURNS

99       Returns true if successful. Returns false and sets error if  there  are
100       invalid arguments or a server or network error.
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EXAMPLE

103       See the example code for mongoc_client_read_command_with_opts.
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AUTHOR

106       MongoDB, Inc
107

109       2017-present, MongoDB, Inc
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1141.20.0                           Nov 1M8O,NG2O0C2_1DATABASE_READ_COMMAND_WITH_OPTS(3)
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