cache_clear_all
Definition
cache_clear_all($cid = NULL, $wildcard = false)
drupal/includes/bootstrap.inc, line 395
Description
Expire data from the cache.
Parameters
$cid If set, the cache ID to delete. Otherwise, all cache entries that can expire are deleted.
$wildcard If set to true, the $cid is treated as a substring to match rather than a complete ID.
Code
function cache_clear_all($cid = NULL, $wildcard = false) {
global $user;
if (empty($cid)) {
if (variable_get('cache_lifetime', 0)) {
// We store the time in the current user's $user->cache variable which
// will be saved into the sessions table by sess_write(). We then
// simulate that the cache was flushed for this user by not returning
// cached data that was cached before the timestamp.
$user->cache = time();
$cache_flush = variable_get('cache_flush', 0);
if ($cache_flush == 0) {
// This is the first request to clear the cache, start a timer.
variable_set('cache_flush', time());
}
else if (time() > ($cache_flush + variable_get('cache_lifetime', 0))) {
// Clear the cache for everyone, cache_flush_delay seconds have
// passed since the first request to clear the cache.
db_query("DELETE FROM {cache} WHERE expire != %d AND expire < %d", CACHE_PERMANENT, time());
variable_set('cache_flush', 0);
}
}
else {
// No minimum cache lifetime, flush all temporary cache entries now.
db_query("DELETE FROM {cache} WHERE expire != %d AND expire < %d", CACHE_PERMANENT, time());
}
}
else {
if ($wildcard) {
db_query("DELETE FROM {cache} WHERE cid LIKE '%%%s%%'", $cid);
}
else {
db_query("DELETE FROM {cache} WHERE cid = '%s'", $cid);
}
}
}