Diese Seite bei php.net
The PHP manual text and comments are covered by the Creative Commons Attribution 3.0 License © the PHP Documentation Group - Impressum - mail("TO:Reinhard Neidl",...)
(PECL memcache >= 0.2.0)
Memcache::replace — Replace value of the existing item
Memcache::replace() should be used to replace value of existing item with key. In case if item with such key doesn't exists, Memcache::replace() returns FALSE. For the rest Memcache::replace() behaves similarly to Memcache::set(). Also you can use memcache_replace() function.
The key that will be associated with the item.
The variable to store. Strings and integers are stored as is, other types are stored serialized.
Use MEMCACHE_COMPRESSED to store the item compressed (uses zlib).
Expiration time of the item. If it's equal to zero, the item will never expire. You can also use Unix timestamp or a number of seconds starting from current time, but in the latter case the number of seconds may not exceed 2592000 (30 days).
Gibt bei Erfolg TRUE zurück. Im Fehlerfall wird FALSE zurückgegeben.
Beispiel #1 Memcache::replace() example
<?php
$memcache_obj = memcache_connect('memcache_host', 11211);
/* procedural API */
memcache_replace($memcache_obj, "test_key", "some variable", false, 30);
/* OO API */
$memcache_obj->replace("test_key", "some variable", false, 30);
?>
This page mentions that replace should be used rather than set, but gives no reason. Best information I could find was a comment by 'argyleblanket' on the set page. (http://www.php.net/manual/en/memcache.set.php#84032)
"Using set more than once for the same key seems to have unexpected results - it does not behave as a "replace," but instead seems to "set" more than one value for the same key. "get" may return any of the values.
This was tested on a multiple-server setup - behaviour may be different if you only have one server. "
Diese Seite bei php.net