cache_clear_all
Definition
cache_clear_all($cid = NULL, $table = NULL, $wildcard = FALSE)
drupal/includes/cache.inc, line 146
Description
Expire data from the cache. If called without arguments, expirable entries will be cleared from the cache_page and cache_block tables.
Parameters
$cid If set, the cache ID to delete. Otherwise, all cache entries that can expire are deleted.
$table If set, the table $table to delete from. Mandatory argument if $cid is set.
$wildcard If set to TRUE, the $cid is treated as a substring to match rather than a complete ID. The match is a right hand match. If '*' is given as $cid, the table $table will be emptied.
Code
function cache_clear_all($cid = NULL, $table = NULL, $wildcard = FALSE) {
global $user;
if (!isset($cid) && !isset($table)) {
// Clear the block cache first, so stale data will
// not end up in the page cache.
cache_clear_all(NULL, 'cache_block');
cache_clear_all(NULL, 'cache_page');
return;
}
if (empty($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 = REQUEST_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', REQUEST_TIME);
}
elseif (REQUEST_TIME > ($cache_flush + variable_get('cache_lifetime', 0))) {
// Clear the cache for everyone, cache_flush_delay seconds have
// passed since the first request to clear the cache.
db_delete($table)
->condition('expire', CACHE_PERMANENT, '<>')
->condition('expire', REQUEST_TIME, '<')
->execute();
variable_set('cache_flush', 0);
}
}
else {
// No minimum cache lifetime, flush all temporary cache entries now.
db_delete($table)
->condition('expire', CACHE_PERMANENT, '<>')
->condition('expire', REQUEST_TIME, '<')
->execute();
}
}
else {
if ($wildcard) {
if ($cid == '*') {
db_delete($table)->execute();
}
else {
db_delete($table)
->condition('cid', $cid . '%', 'LIKE')
->execute();
}
}
else {
db_delete($table)
->condition('cid', $cid)
->execute();
}
}
}