Memcached::add
(PECL memcached >= 0.1.0)
Memcached::add — Add an item under a new key
Описание
Memcached::add() is similar to
Memcached::set(), but the operation fails if the
key already exists on the server.
Список параметров
-
key -
Ключ, под которым сохраняется значение.
-
value -
Сохраняемое значение.
-
expiration -
Время хранения объекта, по умолчанию равно 0. Для более подробной информации смотрите Время хранения объекта.
Возвращаемые значения
Возвращает TRUE в случае успешного завершения или FALSE в случае возникновения ошибки.
The Memcached::getResultCode() will return
Memcached::RES_NOTSTORED if the key already exists.
Смотрите также
- 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
- Функция Memcached::add() - Add an item under a new key
- Функция Memcached::addByKey() - Add an item under a new key on a specific server
- Функция Memcached::addServer() - Add a server to the server pool
- Функция Memcached::addServers() - Add multiple servers to the server pool
- Функция Memcached::append() - Append data to an existing item
- Функция Memcached::appendByKey() - Append data to an existing item on a specific server
- Функция Memcached::cas() - Compare and swap an item
- Функция Memcached::casByKey() - Compare and swap an item on a specific server
- Функция Memcached::__construct() - Create a Memcached instance
- Функция Memcached::decrement() - Decrement numeric item's value
- Функция Memcached::decrementByKey() - Decrement numeric item's value, stored on a specific server
- Функция Memcached::delete() - Delete an item
- Функция Memcached::deleteByKey() - Delete an item from a specific server
- Функция Memcached::deleteMulti() - Delete multiple items
- Функция Memcached::deleteMultiByKey() - Delete multiple items from a specific server
- Функция Memcached::fetch() - Fetch the next result
- Функция Memcached::fetchAll() - Fetch all the remaining results
- Функция Memcached::flush() - Invalidate all items in the cache
- Функция Memcached::get() - Retrieve an item
- Функция Memcached::getAllKeys() - Gets the keys stored on all the servers
- Функция Memcached::getByKey() - Retrieve an item from a specific server
- Функция Memcached::getDelayed() - Request multiple items
- Функция Memcached::getDelayedByKey() - Request multiple items from a specific server
- Функция Memcached::getMulti() - Retrieve multiple items
- Функция Memcached::getMultiByKey() - Retrieve multiple items from a specific server
- Функция Memcached::getOption() - Retrieve a Memcached option value
- Функция Memcached::getResultCode() - Return the result code of the last operation
- Функция Memcached::getResultMessage() - Return the message describing the result of the last operation
- Функция Memcached::getServerByKey() - Map a key to a server
- Функция Memcached::getServerList() - Get the list of the servers in the pool
- Функция Memcached::getStats() - Get server pool statistics
- Функция Memcached::getVersion() - Get server pool version info
- Функция Memcached::increment() - Increment numeric item's value
- Функция Memcached::incrementByKey() - Increment numeric item's value, stored on a specific server
- Функция Memcached::isPersistent() - Check if a persitent connection to memcache is being used
- Функция Memcached::isPristine() - Check if the instance was recently created
- Функция Memcached::prepend() - Prepend data to an existing item
- Функция Memcached::prependByKey() - Prepend data to an existing item on a specific server
- Функция Memcached::quit() - Close any open connections
- Функция Memcached::replace() - Replace the item under an existing key
- Функция Memcached::replaceByKey() - Replace the item under an existing key on a specific server
- Функция Memcached::resetServerList() - Clears all servers from the server list
- Функция Memcached::set() - Store an item
- Функция Memcached::setByKey() - Store an item on a specific server
- Функция Memcached::setMulti() - Store multiple items
- Функция Memcached::setMultiByKey() - Store multiple items on a specific server
- Функция Memcached::setOption() - Set a Memcached option
- Функция Memcached::setOptions() - Set Memcached options
- Функция Memcached::setSaslAuthData() - Set the credentials to use for authentication
- Функция Memcached::touch() - Set a new expiration on an item
- Функция Memcached::touchByKey() - Set a new expiration on an item on a specific server
Коментарии
<?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");
}
?>
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.