按特定ID排序，而不是按列总数排序 [英] Ordering by specific id and not by total of column

问题描述

  SELECT COUNT（pilotid）作为总数，depicao FROM db_pireps 
 GROUP BY depicao ORDER BY total DESC 
 LIMIT 5 
  

在我的HTML中， （$ fav_deps as $ departure）

c> $ fav_deps = DB :: get_results（$ dep_query）;

在foreach中，每行记录都会生成一行。一栏应计算飞行员离开指定机场的次数。但是， $ departure-> total 假设实际从机场出发的总出发量，我想这样做是为了计算出 pilotid ，在这种情况下，它是 depicao 。

 < td width =20％><？php echo $ departure-> ;总; ？>< / TD> 
  

另外，我附上了一张屏幕截图来说明db_pireps是如何构建的。

解决方案

您也应该通过pilotid进行分组，然后选择该列，这样您就可以得到您想要的结果。

  SELECT COUNT（pilotid）as total，depicao，pilotid FROM db_pireps GROUP 
 BY depicao，pilotid ORDER BY total DESC LIMIT 5 
  

如果经过这样的结果， $ departure-> total 将仅包含给定飞行员的值。

I have this query in a PHP file:

SELECT COUNT(pilotid) as total, depicao FROM db_pireps
GROUP BY depicao ORDER BY total DESC
LIMIT 5

In my HTML, I then get the results from the database and use foreach($fav_deps as $departure)

$fav_deps = DB::get_results($dep_query);

Inside the foreach, a row generates for each record. One column should calculate the amount of times the pilot has departed from a specified airport. However, $departure->total assumes the actual total departures from the airport, and I'd like to make it so it calculates the total departures for a pilotid from a specified airport, which in this case is depicao. How can I achieve this?

<td width="20%"><?php echo $departure->total; ?></td>

Additionally, I have attached a screenshot to illustrate how db_pireps is structured.

解决方案

You should group by pilotid too, and select that column, this way you get the result you wanted.

SELECT COUNT(pilotid) as total, depicao, pilotid FROM db_pireps GROUP
BY depicao, pilotid ORDER BY total DESC LIMIT 5

If you go through the result of this, $departure->total will contain the value only for a given pilot.

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