(PECL mongo >=0.9.0)
Instances of this class are used to interact with a database. To get a database:
Beispiel #1 Selecting a database
<?php
$m = new MongoClient(); // connect
$db = $m->selectDB("example");
?>
A few unusual, but valid, database names: "null", "[x,y]", "3", "\"", "/".
Unlike collection names, database names may contain "$".
$preserve_cloned_files
= FALSE
[, bool $backup_original_files
= FALSE
]] ) : arrayMongoDB::PROFILING_OFF
MongoDB::PROFILING_SLOW
MongoDB::PROFILING_ON
The number of servers to replicate a change to before returning success.
Inherited by instances of MongoCollection derived
from this. w
functionality is only available in
version 1.5.1+ of the MongoDB server and 1.0.8+ of the driver.
w
is used whenever you need to adjust the
acknowledgement level
(MongoCollection::insert(),
MongoCollection::update(),
MongoCollection::remove(),
MongoCollection::save(), and
MongoCollection::ensureIndex() all support this
option). With the default value (1), an acknowledged operation will return once
the database server has the operation. If the server goes down before
the operation has been replicated to a secondary, it is possible to lose
the operation forever. Thus, you can specify w
to be
higher than one and guarantee that at least one secondary has the
operation before it is considered successful.
For example, if w
is 2, the primary and one secondary
must have a record of the operation or the driver will throw a
MongoCursorException. It is tempting to set
w
to the total number of secondaries + primary, but
then if one secondary is down the operation will fail and an exception
will be thrown, so usually w=2
is safest (primary and
one secondary).
The number of milliseconds to wait for MongoDB::$w
replications to take place. Inherited by instances of
MongoCollection derived from this.
w
functionality is only available in version 1.5.1+ of
the MongoDB server and 1.0.8+ of the driver.
Unless wtimeout
is set, the server waits forever for
replicating to w
servers to finish. The driver
defaults to waiting for 10 seconds, you can change this value to alter
its behavior.
MongoDB core docs on » databases.