MongoDB\Driver\Server::executeReadCommand

(mongodb >=1.4.0)

MongoDB\Driver\Server::executeReadCommandExecute a database command that reads on this server

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final public MongoDB\Driver\Server::executeReadCommand ( string $db , MongoDB\Driver\Command $command [, array $options = array() ] ) : MongoDB\Driver\Cursor

Executes the command on this server.

This method will apply logic that is specific to commands that read (e.g. » count) and take the MongoDB server version into account. The "readConcern" option will default to the corresponding value from the MongoDB Connection URI.

Note: The "readPreference" option does not control the server to which the driver issues the operation; it will always be executed on this server object. Instead, it may be used when issuing the operation to a secondary (from a replica set connection, not standalone) or mongos node to ensure that the driver sets the wire protocol accordingly or adds the read preference to the operation, respectively.

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db (string)

The name of the database on which to execute the command.

command (MongoDB\Driver\Command)

The command to execute.

options

options
Option Type Description
readConcern MongoDB\Driver\ReadConcern

A read concern to apply to the operation.

This option is available in MongoDB 3.2+ and will result in an exception at execution time if specified for an older server version.

readPreference MongoDB\Driver\ReadPreference

A read preference to use for selecting a server for the operation.

session MongoDB\Driver\Session

A session to associate with the operation.

Warning

If you are using a "session" which has a transaction in progress, you cannot specify a "readConcern" or "writeConcern" option. This will result in an MongoDB\Driver\Exception\InvalidArgumentException being thrown. Instead, you should set these two options when you create the transaction with MongoDB\Driver\Session::startTransaction().

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Returns MongoDB\Driver\Cursor on success.

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