Yac::delete
(PECL yac >= 1.0.0)
Yac::delete — Remove items from cache
Description
Removes one or more items from the cache.
Note:
Deletion is implemented by marking the entry expired rather than
clearing its slot: the entry immediately stops being readable, but
the slot stays occupied until the same key is stored again or a
later write reclaims the slot. As a result, the used-slot count
reported by Yac::info() does not decrease
after a deletion, and Yac::dump() still
lists the deleted entry until its slot is recycled; a non-zero
ttl in the past marks a deleted or expired
entry, so when inspecting the output of
Yac::dump(), such entries have to be
filtered out by the caller.
Parameters
key-
A string key, or an array of keys to be
removed.
delay-
Number of seconds before the item becomes invalid. When omitted or
0, the item is invalidated immediately. A positive
value keeps the item readable for that many seconds before it
expires.
Return Values
Returns true on success, or false if the key was not present in
the cache. Because a deletion only marks the entry expired, a key
that was deleted but not yet overwritten still counts as present:
deleting the same key again returns true.
When an array of keys is given, true is returned
only if every key was present; if any key is missing, false is
returned.
Examples
Example #1 Yac::delete() example
<?php
$yac = new Yac();
$yac->set("foo", "bar");
var_dump($yac->delete("foo")); // bool(true): marked expired
var_dump($yac->get("foo")); // bool(false): a miss from now on
var_dump($yac->delete("foo")); // bool(true) again: the slot has not
// been overwritten yet
var_dump($yac->delete("never")); // bool(false): was never stored
// a deletion does not free the slot: slots_used does not drop, and
// the expired entry still shows up in the dump
var_dump($yac->info()["slots_used"]); // int(1)
print_r($yac->dump()); // "foo" is still listed; its ttl
// is in the past
?>
Example #2 Delayed deletion
<?php
$yac = new Yac();
// keep the entry readable for 60 more seconds before it expires
$yac->set("tmp", "value");
var_dump($yac->delete("tmp", 60)); // bool(true)
?>
Example #3 Deleting multiple keys at once
<?php
$yac = new Yac();
$yac->set("tmp", "value");
// returns true only when every key was present
var_dump($yac->delete(array("tmp", "nope"))); // bool(false): "nope" missing
?>
Yac::__construct
Yac