apc_sma_info
Don't save empty arrays and empty values. Sometimes, you can get wrong apc_exists($someKey) result, that this key doesn't exists.
apc_store
(PECL apc >= 3.0.0)
apc_store — Cache a variable in the data store
Description
Cache a variable in the data store.
Note: Unlike many other mechanisms in PHP, variables stored using apc_store() will persist between requests (until the value is removed from the cache).
Parameters
-
key -
Store the variable using this name.
keys are cache-unique, so storing a second value with the samekeywill overwrite the original value. -
var -
The variable to store
-
ttl -
Time To Live; store
varin the cache forttlseconds. After thettlhas passed, the stored variable will be expunged from the cache (on the next request). If nottlis supplied (or if thettlis 0), the value will persist until it is removed from the cache manually, or otherwise fails to exist in the cache (clear, restart, etc.). -
values -
Names in key, variables in value.
Return Values
Returns TRUE on success or FALSE on failure.
Second syntax returns array with error keys.
Examples
Example #1 A apc_store() example
<?php
$bar = 'BAR';
apc_store('foo', $bar);
var_dump(apc_fetch('foo'));
?>
The above example will output:
string(3) "BAR"
See Also
- apc_add() - Cache a new variable in the data store
- apc_fetch() - Fetch a stored variable from the cache
- apc_delete() - Removes a stored variable from the cache
add a note
User Contributed Notes
apc_store
danil dot gazizov at gmail dot com
03-Feb-2012 11:49
pere dot cil dot remove dot this at wanadoo dot fr
09-Dec-2011 01:49
Note that caching resources is not possible; even if the apc cache doesn't seems to call the serialize / unserialize functions, that doesn't means that resources can be cached!
Small non-working example:
<?php
// Setter code
$r = fopen( '/tmp/test.txt', 'r' );
var_dump( $r );
apc_store( 'test', $r );
?>
<?php
// Getter code
$d = apc_fetch( 'test' );
var_dump( $d );
echo fread( $d, 1024 );
?>
var_dump( $d ) returns Resource #n of type (Unknown). The resource is still here, but unavailable.
Dominik Deobald / Interdose
17-Nov-2010 11:17
It might be interesting to note that storing an object in the cache does not serialize the object, i.e. does not call the __sleep()/__wakeup() or serialize()/unserialize() methods.
TaRaKa
25-Aug-2010 01:32
Note APC version 3.1.3 there is a bug (http://pecl.php.net/bugs/bug.php?id=16814) that will display a cache slam averted warning for all writes to a cache var that exists. Slam checking can be disabled by setting apc.slam_defense = 0.
eda-qa at disemia dot com
05-Jan-2010 07:40
Note that the TTL only takes effect when you attempt to access the variable again (at least in my version). That is, just issuing a new request to a page won't clear outdated items -- you have to call apc_fetch on that specific item.
If you call apc_info after the TTL of an item it will still be listed.
This is important if you are expecting items to be cleared to conserve memory.
sebastian at 7val dot com
10-Mar-2008 12:53
Note that since APC 3.0.15 or 3.0.16, the time-to-live-feature does not work within the same request (see http://pecl.php.net/bugs/bug.php?id=13331).
JaskaS
01-Mar-2007 06:06
if you want to store array of objects in apc use ArrayObject wrapper (PHP5).
<?php
$objs = array();
$objs[] = new TestClass();
$objs[] = new TestClass();
$objs[] = new TestClass();
//Doesn't work
apc_store('objs',$objs,60);
$tmp = apc_fetch('objs');
print_r($tmp);
//Works
apc_store('objs',new ArrayObject($objs),60);
$tmp = apc_fetch('objs');
print_r($tmp->getArrayCopy());
?>
Roberto Spadim
12-Jan-2007 02:11
be sure that setting FALSE values can be wrong returned from fetch since fetch return FALSE on errors
php at tequilasolutions dot com
03-Nov-2006 03:45
Seems to be no (easy) way at the to know how old a value fetched is and to check whether it is out of date.
I've made these wrappers so that you can fetch and store values based on a udt returned from get_last_modified_date() which should return a udt of when your data was last changed, and hence needs junking out of the cache.
<?php
function apc_fetch_udt($key){
$g = apc_fetch($key);
if ($g){
list($udt,$val) = $g;
if (get_last_modified_date()<$udt) {
$val = unserialize($val);
return $val;
} else {
apc_delete($key);
}
}
}
function apc_store_udt($key,$g){
$udt = time();
$g = serialize($g);
$apc = array($udt,$g);
apc_store($key, $apc);
}
?>
Sudhee
30-Oct-2006 04:09
It should be noted that apc_store appears to only store one level deep. So if you have an array of arrays, and you store it. When you pull it back out with apc_fetch it will only have the top level row of keys with nulls as the values of each key.
Solution to this, is to serialize the data before storing it in the cache and unserialize it while retrieving from the cache.