Question

$image=mysql_query("select * from carad order by carAdID DESC LIMIT 10"); 

    while($row=mysql_fetch_array($image)) 
    { 
      $getimage=mysql_query("select * from carimage where carAdID='".$row["carAdID"]."' LIMIT 1"); 
      while($getimagerow=mysql_fetch_array($getimage)) 
      { 
       echo(''); 
       echo('<a href="#" ><div class="simages"><img src="'.substr($getimagerow["carImageUrl"],1).'" width="600" height="400" /><div class="SliderContent">'.$row["catalogPrice"].'</div></div></a>'); 
      } 
    } 

我使用兩個查詢一個是前while循環和while循環的ID是來自於第一個查詢有沒有打電話給這些查詢在一個單一的查詢，使其優化任何最好的方法。

Answer 1

試試這個：

SELECT ci.* 
FROM carimage ci 
INNER JOIN 
(
    select * 
    from carad 
    order by carAdID DESC LIMIT 10 
) c ON ci.carAdID = c.carAdID 
--May be you need to add LIMIT here as well