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MongoDB C++ Driver
mongocxx-3.0.0
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A class to represent the read concern. More...
#include <read_concern.hpp>
Public Types | |
| enum | level |
| A class to represent the read concern level. More... | |
Public Member Functions | |
| read_concern () | |
| Constructs a new read_concern with default acknowledge_level of k_server_default. More... | |
| read_concern (const read_concern &) | |
| Copy constructs a read_concern. | |
| read_concern & | operator= (const read_concern &) |
| Copy assigns a read_concern. | |
| read_concern (read_concern &&) noexcept | |
| Move constructs a read_concern. | |
| read_concern & | operator= (read_concern &&) noexcept |
| Move assigns a read_concern. | |
| ~read_concern () | |
| Destroys a read_concern. | |
| void | acknowledge_level (level rc_level) |
| Sets the read concern level. More... | |
| level | acknowledge_level () const |
| Gets the current read concern level. More... | |
| void | acknowledge_string (stdx::string_view rc_string) |
| Sets the read concern string. More... | |
| stdx::string_view | acknowledge_string () const |
| Gets the current read concern string. More... | |
A class to represent the read concern.
Read concern can be set at the client, database, or collection level. The read concern can also be provided via connection string, and will be parsed and set on the client constructed for the URI.
For the WiredTiger storage engine, MongoDB 3.2 introduced the readConcern option for replica sets and replica set shards. The readConcern option allows clients to choose a level of isolation for their reads. You can specify a readConcern of "majority" to read data that has been written to a majority of nodes and thus cannot be rolled back. By default, MongoDB uses a readConcern of "local" which does not guarantee that the read data would not be rolled back.
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strong |
A class to represent the read concern level.
| mongocxx::read_concern::read_concern | ( | ) |
Constructs a new read_concern with default acknowledge_level of k_server_default.
The k_server_default acknowledge level has an empty acknowledge_string. Queries that run with this read_concern will use the server's default read_concern instead of specifying one.
| void mongocxx::read_concern::acknowledge_level | ( | level | rc_level | ) |
Sets the read concern level.
| rc_level | Either k_local, k_majority, or k_server_default. |
| std::invalid_argument | if rc_level is not k_local, k_majority, or k_server_default. |
| level mongocxx::read_concern::acknowledge_level | ( | ) | const |
Gets the current read concern level.
If this was set with acknowledge_string to anything other than "local", "majority", or an empty string, this will return k_unknown.
| void mongocxx::read_concern::acknowledge_string | ( | stdx::string_view | rc_string | ) |
Sets the read concern string.
One of "local", "majority", or "".
| rc_string | The read concern string. |
| stdx::string_view mongocxx::read_concern::acknowledge_string | ( | ) | const |
Gets the current read concern string.
If the read concern level was set with acknowledge_level, this will return either "local", "majority", or an empty string for k_server_default.
1.8.10
