多个mysql查询与group by

Question

目前我正在考虑我的代码，目前我有

$query="SELECT DISTINCT TRIPID FROM trips_info WHERE userid=$userid";
    $results = $dbh->query($query)->fetchAll();
        foreach ($results as $i => $row)
        {
            $iquery="SELECT COUNT(id) FROM trips_data WHERE userid=$userid AND tripid=$row[0]";
            $iiqu="SELECT COUNT(id) FROM trips_data WHERE userid=$userid AND not killcount=0 AND tripid=$row[0]";
            $irow=$dbh->query($iquery)->fetch();
            $iirow=$dbh->query($iiqu)->fetch();
            array_push($tripsdata, $row[0]);
            array_push($tripsdata, $irow[0]);
            array_push($tripsdata, $iirow[0]);
        }

我很清楚，必须有一种方法可以获得一个pdo，其中包含循环中多个数据库连接所需的所有信息。 这是我到目前为止（这是行不通的）

SELECT (
   (SELECT COUNT(id) as no FROM trips_data WHERE userid=1),
   (SELECT COUNT(id) as no FROM trips_data WHERE userid=1 AND not killcount=0)
) group by trips_data.tripid

我的问题是你如何在这种查询中添加group by语句？

我希望得到的是

tripid points kills，1 5322 109,2 83939 17

Answer 1

如果你有什么“killcount”为null而不是0，那就是

SELECT tripid, count(1), count(killcount) 
FROM trips_info ti, trips_data td WHERE ti.userid=? AND td.tripid=ti.tripid
GROUP BY td.tripid

Answer 2

我正在假设您的数据库架构，但我认为这可以成为一个查询

SELECT
  ti.tripid, 
  COUNT(td_a) as 'trip_count_1', 
  COUNT(tb_b) as 'trip_count_2' 
FROM
  trips_info AS ti
INNER JOIN
  trips_data AS td_a ON td_a.tripid = ti.id
INNER JOIN
  trips_data AS td_b ON td_b.tripid = ti.id AND td_b.killcount > 0
WHERE
 ti.userid = ?

Answer 3

谢谢你所有的帮助我最终采取了不同的路线并得到了这个，这很好

SELECT  
        tripid,
        SUM(CASE WHEN killcount >0 THEN 1 ELSE 0 END) AS kills, 
        count(id) AS points 
        FROM trips_data  
        WHERE userid=$userid
        GROUP BY tripid";