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(PECL mongo >=1.3.0)
MongoDB::setReadPreference — Set the read preference for this database
$read_preference
[, array $tags
] )read_preference
The read preference mode: MongoClient::RP_PRIMARY
, MongoClient::RP_PRIMARY_PREFERRED
, MongoClient::RP_SECONDARY
, MongoClient::RP_SECONDARY_PREFERRED
, or MongoClient::RP_NEAREST
.
tags
An array of zero or more tag sets, where each tag set is itself an array of criteria used to match tags on replica set members.
Returns TRUE
on success, or FALSE
otherwise.
Emits E_WARNING
if either parameter is invalid, or if one or more tag sets are provided with the MongoClient::RP_PRIMARY
read preference mode.
Example #1 MongoDB::setReadPreference() tag set array syntax example
<?php
$m = new MongoClient ();
$db = $m -> test ;
// Prefer the nearest server in the "east" data center also used for reporting,
// but fall back to a server in the "west" data center
$db -> setReadPreference ( MongoClient :: RP_NEAREST , array(
array( 'dc' => 'east' , 'use' => 'reporting' ),
array( 'dc' => 'west' ),
));
?>