php图形无法正常运行

Question

我一直试图修复此图表已有一段时间了。谁能告诉我代码或查询有什么问题？

   $graphTimeOne = time(); 
   for($graphTimeOne = 29; $graphTimeOne >= 0; $graphTimeOne--){    
   $graphTimestampOne = mktime(0, 0, 0, date("n"), date("j") - $graphTimeOne, date("Y"));   
   $graphOneResult = mysql_query("SELECT COUNT(id) FROM id WHERE timestamp >= UNIX_TIMESTAMP(DATE_SUB(NOW(), INTERVAL 29 DAY)) GROUP BY DAY(FROM_UNIXTIME(timestamp))");            
   $User = mysql_result($graphOneResult, 0, 0);     
   mysql_free_result($graphOneResult);      
   $graphBarOne[$bar_nr] = $User; // Im Array Speichern     
   $bar_title[$bar_nr] = date("Y-m-d", $graphTimestampOne);

为什么我的代码不能使用mysql查询？