/**
* Increments an integer config value directly in the database.
*
* Using this method instead of setting the new value directly avoids race
* conditions and unlike set_atomic it cannot fail.
*
* @param string $key The configuration option's name
* @param int $increment Amount to increment by
* @param bool $use_cache Whether this variable should be cached or if it
* changes too frequently to be efficiently cached.
*/
function increment($key, $increment, $use_cache = true)
{
if (!isset($this->config[$key])) {
$this->set($key, '0', $use_cache);
}
$sql_update = $this->db->cast_expr_to_string($this->db->cast_expr_to_bigint('config_value') . ' + ' . (int) $increment);
$this->db->sql_query('UPDATE ' . $this->table . '
SET config_value = ' . $sql_update . "\n\t\t\tWHERE config_name = '" . $this->db->sql_escape($key) . "'");
if ($use_cache) {
$this->cache->destroy('config');
}
$this->config[$key] += $increment;
}
