Memcached::set()

(PECL memcached >= 0.1.0)

存储一个元素

说明

publicMemcached::set(string $key, mixed $value[,int $expiration]): bool

Memcached::set()将$value存储在一个memcached服务器上的$key下。$expiration参数用于控制值的过期时间。

值可以是任何有效的非资源型php类型，因为资源类型不能被序列化存储。如果Memcached::OPT_COMPRESSION选项开启，序列化的值同样会被压缩存储。

参数

$key

用于存储值的键名。

$value

存储的值。

$expiration

到期时间，默认为 0。更多信息请参见到期时间。

返回值

成功时返回TRUE，或者在失败时返回FALSE。如需要则使用Memcached::getResultCode()。

范例

Example #1 Memcached::set()示例

<?php
$m = new Memcached();
$m->addServer('localhost', 11211);
$m->set('int', 99);
$m->set('string', 'a simple string');
$m->set('array', array(11, 12));
/* 'object'这个key将在5分钟后过期 */
$m->set('object', new stdclass, time() + 300);
var_dump($m->get('int'));
var_dump($m->get('string'));
var_dump($m->get('array'));
var_dump($m->get('object'));
?>

以上例程的输出类似于：

int(99)
string(15) "a simple string"
array(2) {
  [0]=>
  int(11)
  [1]=>
  int(12)
}
object(stdClass)#1 (0) {
}

参见

• Memcached::setByKey() Store an item on a specific server
• Memcached::add() 向一个新的key下面增加一个元素
• Memcached::replace() 替换已存在key下的元素

@PeterN
You said that this was wrong:
$m->set('object', new stdclass, time() + 300);
And instead this is the correct way:
$m->set('object', new stdclass, 300);
When actually, they are both correct. Expiration looks at the time given, if the number is less than or equal to 30 days(60 * 60 * 24 * 30 = 2,592,000), then it expires in that many seconds. If the number is greater than 30 days, then it expires at that UNIX time.

In the example it shows:
/* expire 'object' key in 5 minutes */
$m->set('object', new stdclass, time() + 300);
But this is wrong.
It will not expire, at least, not for a long long time.
So instead of time() + seconds, you use:
$m->set('object', new stdclass, 300);
And it will correctly expire after 5 minutes.
Note: Using memcached 2.1.0 stable through PECL.

Unlike Memcache, Memcached will not replace spaces in keys with underscores for you, and will instead send the key as provided which will cause an error that can result in keys and values being mismatched. You can avoid this problem by removing/replacing spaces before storage or setting the option Memcached::OPT_BINARY_PROTOCOL to true.

00 = MEMCACHED_SUCCESS
01 = MEMCACHED_FAILURE
02 = MEMCACHED_HOST_LOOKUP_FAILURE // getaddrinfo() and getnameinfo() only
03 = MEMCACHED_CONNECTION_FAILURE
04 = MEMCACHED_CONNECTION_BIND_FAILURE // DEPRECATED see MEMCACHED_HOST_LOOKUP_FAILURE
05 = MEMCACHED_WRITE_FAILURE
06 = MEMCACHED_READ_FAILURE
07 = MEMCACHED_UNKNOWN_READ_FAILURE
08 = MEMCACHED_PROTOCOL_ERROR
09 = MEMCACHED_CLIENT_ERROR
10 = MEMCACHED_SERVER_ERROR // Server returns "SERVER_ERROR"
11 = MEMCACHED_ERROR // Server returns "ERROR"
12 = MEMCACHED_DATA_EXISTS
13 = MEMCACHED_DATA_DOES_NOT_EXIST
14 = MEMCACHED_NOTSTORED
15 = MEMCACHED_STORED
16 = MEMCACHED_NOTFOUND
17 = MEMCACHED_MEMORY_ALLOCATION_FAILURE
18 = MEMCACHED_PARTIAL_READ
19 = MEMCACHED_SOME_ERRORS
20 = MEMCACHED_NO_SERVERS
21 = MEMCACHED_END
22 = MEMCACHED_DELETED
23 = MEMCACHED_VALUE
24 = MEMCACHED_STAT
25 = MEMCACHED_ITEM
26 = MEMCACHED_ERRNO
27 = MEMCACHED_FAIL_UNIX_SOCKET // DEPRECATED
28 = MEMCACHED_NOT_SUPPORTED
29 = MEMCACHED_NO_KEY_PROVIDED /* Deprecated. Use MEMCACHED_BAD_KEY_PROVIDED! */
30 = MEMCACHED_FETCH_NOTFINISHED
31 = MEMCACHED_TIMEOUT
32 = MEMCACHED_BUFFERED
33 = MEMCACHED_BAD_KEY_PROVIDED
34 = MEMCACHED_INVALID_HOST_PROTOCOL
35 = MEMCACHED_SERVER_MARKED_DEAD
36 = MEMCACHED_UNKNOWN_STAT_KEY
37 = MEMCACHED_E2BIG
38 = MEMCACHED_INVALID_ARGUMENTS
39 = MEMCACHED_KEY_TOO_BIG
40 = MEMCACHED_AUTH_PROBLEM
41 = MEMCACHED_AUTH_FAILURE
42 = MEMCACHED_AUTH_CONTINUE
43 = MEMCACHED_PARSE_ERROR
44 = MEMCACHED_PARSE_USER_ERROR
45 = MEMCACHED_DEPRECATED
46 = MEMCACHED_IN_PROGRESS
47 = MEMCACHED_SERVER_TEMPORARILY_DISABLED
48 = MEMCACHED_SERVER_MEMORY_ALLOCATION_FAILURE
49 = MEMCACHED_MAXIMUM_RETURN /* Always add new error code before */
11 = MEMCACHED_CONNECTION_SOCKET_CREATE_FAILURE = MEMCACHED_ERROR

The method correctly returns false if you set the value to false. This means that in order to have proper fault checking mechanism in place you need to check the result code.
<?php
$Memcached = new Memcached();
$Memcached->addServer('localhost', 11211);
$Memcached->set('key', false);
var_dump($Memcached->get('key'));   // boolean false
var_dump($Memcached->getResultCode()); // int 0 which is Memcached::RES_SUCCESS 
?>