Note that this operation is atomic, means that it's safe from race condition operation (since memcached is running in single process). You can use this method for locks and can be sure that two requests will not get "true" simultaneously using this method.
Memcached::add
(PECL memcached >= 0.1.0)
Memcached::add — Add an item under a new key
Description
Memcached::add() is similar to
Memcached::set(), but the operation fails if the
key already exists on the server.
Parameters
-
key -
The key under which to store the value.
-
value -
The value to store.
-
expiration -
The expiration time, defaults to 0. See Expiration Times for more info.
Return Values
Returns true on success or false on failure.
The Memcached::getResultCode() will return
Memcached::RES_NOTSTORED if the key already exists.
See Also
- Memcached::addByKey() - Add an item under a new key on a specific server
- Memcached::set() - Store an item
- Memcached::replace() - Replace the item under an existing key
add a note
User Contributed Notes 2 notes
ilya dot chase at yandex dot ru ¶
5 years ago
zhoujunwen888 at 126 dot com ¶
9 years ago
<?php
/**
* Created by PhpStorm.
* User: zhoujunwen
* Date: 15/6/17
* Time: 下午4:51
*/
$mem = new Memcached();
$mem->addServer('127.0.0.1',11211);
if( $mem->add("mystr","this is a memcache test!",3600)){
echo '原始数据缓存成功!';
}else{
echo '数据已存在：'.$mem->get("mystr");
}
?>
