(PECL memcached >= 0.1.0)
Memcached::increment — Increment numeric item's value
$key
[, int $offset = 1
[, int $initial_value = 0
[, int $expiry = 0
]]] )
Memcached::increment() increments a numeric item's value
by the specified offset. If the item's value is not
numeric, an error will result.
Memcached::increment() will set the item to the
initial_value parameter if the key doesn't exist.
keyThe key of the item to increment.
offsetThe amount by which to increment the item's value.
initial_valueThe value to set the item to if it doesn't currently exist.
expiryThe expiry time to set on the item.
Returns new item's value on success or FALSE on failure.
Example #1 Memcached::increment() example
<?php
$m = new Memcached();
$m->addServer('localhost', 11211);
$m->set('counter', 0);
$m->increment('counter');
$n = $m->increment('counter', 10);
var_dump($n);
$m->set('counter', 'abc');
$n = $m->increment('counter');
// ^ will fail due to item value not being numeric
var_dump($n);
?>
The above example will output:
int(11) bool(false)
Spent a long time frustrated with this. If you read the patch notes carefully:
- Make increment/decrement initialize value when it is not available (when using binary protocol).
If you dont have the opt binary protocol set the arguments for initial value just return an error 38 - INVALID ARGUMENTS. This is not documented.
PECL memcached < 0.2.0
public int Memcached::increment ( string $key [, int $offset = 1 ] )
If it'll save others some head-scratching, the PECL Memcached extension only supports initializing increment (or decrement) values from 2.0.0b2 onwards - i.e. not the version (1.0.2) that comes out of the box with Ubuntu 12.04.
