Memcache::replace Replace value of the existing item &reftitle.description; boolMemcache::replace stringkey mixedvar intflag intexpire 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. &reftitle.parameters; key The key that will be associated with the item. var The variable to store. Strings and integers are stored as is, other types are stored serialized. flag Use MEMCACHE_COMPRESSED to store the item compressed (uses zlib). expire 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). &reftitle.returnvalues; &return.success; &reftitle.examples; replace("test_key", "some variable", false, 30); ?> ]]> &reftitle.seealso; Memcache::set Memcache::add