打开ci 调试

$this -> output -> enable_profiler(TRUE);

$this->db->last_query();
echo "<pre>";   
var_dump($this->db->queries);
$this->db->save_queries = TRUE;
$this -> output -> enable_profiler(TRUE);

______________function 中写redis

function static_version(){
   $cache = init_cache('redis')->redis;
   $static_version = $cache->get('admin/file_static_version');
   if(!$static_version){
      $static_version = date('YmdHis');
      $cache->save('admin/file_static_version', $static_version, 86400);
   }
   return $static_version; 
}