Cache deletion by session_id always fails
|Reported by:||ziba||Owned by:||thomasb|
If caching is enabled, then in program/include/session.inc rcube_sess_destroy calls:
$DB->query("DELETE FROM " . get_table_name('cache') . " WHERE session_id=?", $key);
However, I couldn't find any place where cache.session_id is populated.
On our production systems the cache table was large enough to delay user logins by about 20 seconds while it searched through thousands of Null values.