Memcache::add

Description

bool Memcache::add ( string key, mixed var [, int flag [, int expire]] )

Memcache::add() stores variable var with key only if such key doesn't exist at the server yet. Memcache::add() returns FALSE if such key already exist. For the rest Memcache::add() behaves similarly to Memcache::set().

Also you can use memcache_add() function. See example below.

例子 1. Memcache::add() example


<?php

$memcache_obj = memcache_connect("localhost", 11211);

/* procedural API */
memcache_add($memcache_obj, 'var_key', 'test variable', false, 30);

/* OO API */
$memcache_obj->add('var_key', 'test variable', false, 30);

?>

Memcache::add() returns TRUE on success or FALSE on failure.

See also Memcache::set(), Memcache::replace().

add a note User Contributed Notes

Joel Yliluoma
19-Apr-2006 09:19


Followup to the previous poster:

Instead of replace()+add(), you should of course use set().

adam dot alkins at gmail dot com
13-Feb-2006 01:23


As the documentation notes, this function returns false if it doesn't replace an existing item (You must have added the item before for replace to work). If you're writing a dynamic application which for example caches data from an SQL database, your code should look like this.



<?php



if(!$mc->replace('foo', 'bar'))

{

    $mc->add('foo', 'bar');

}



?>



This ensures that the memcache server is repopulated properly everytime it is restarted.

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