Codeigniter profiler, where are the queries coming from ?

database_DB_driver.php

		// ...

		// Save the  query for debugging
		if ($this->save_queries == TRUE)
		{

			// ADDED: Some backtracing
			$file = '';
			$callstack = debug_backtrace();
			if(count($callstack) >= 2)
			{
				//list($callee) = $callstack[1];
				if (strpos($callstack[1]['file'], BASEPATH)===0)
				{
					$file = 'CI/'.str_replace(BASEPATH, '', $callstack[1]['file']); 
				}
				elseif (strpos($callstack[1]['file'], APPPATH)===0)
				{
					$file = 'APP/'.str_replace(APPPATH, '', $callstack[1]['file']); 
				}
				else
				{
					$file = 'UNKNOWN : '.$callstack[1]['file'];
				}
				$file = "\n#" . $file;
			}

			$this->queries[] = $sql . $file;

		}