Question

我正在加入三张桌子并计算MY SQL FIDDLE。在这个查询中，我想再多计算total_trip，这意味着我已经加入了trip_details表，在这个表中取所有计数即总行程计数，我无法编写子查询。

SELECT COUNT(T.tripId) as Escort_Count,
(
    SELECT COUNT(*) FROM 
    (
        SELECT a.allocationId
        FROM escort_allocation a 
        INNER JOIN cab_allocation c ON a.allocationId = c.allocationId 
        WHERE c.allocationType = 'Adhoc Trip' 
        GROUP BY a.allocationId
    ) AS Ad

) AS Adhoc_Trip_Count 
FROM 
( 
    SELECT a.tripId FROM 
    trip_details a 
    INNER JOIN 
    escort_allocation b 
    ON a.allocationId = b.allocationId 
    GROUP BY a.allocationId 
) AS T

Answer 1

使用以下子查询：

<强>查询：

  SELECT COUNT(T.tripId) as Escort_Count,
  (
      SELECT COUNT(*) FROM 
      (
          SELECT a.allocationId
          FROM escort_allocation a 
          INNER JOIN cab_allocation c ON a.allocationId = c.allocationId 
          WHERE c.allocationType = 'Adhoc Trip' 
          GROUP BY a.allocationId
      ) AS Ad

  ) AS Adhoc_Trip_Count,
  (SELECT COUNT(id) FROM trip_details) as Total_Count
  FROM 
  ( 
      SELECT a.tripId FROM 
      trip_details a 
      INNER JOIN 
      escort_allocation b 
      ON a.allocationId = b.allocationId 
      GROUP BY a.allocationId 
  ) AS T

结果：

Escort_Count   Adhoc_Trip_Count   Total_Trip
5              2                  7

查看：

SQL Fiddle

Answer 2

        SELECT COUNT(DISTINCT Z.allocationId) Escort_Count,SUM(CASE WHEN allocationType='Adhoc Trip' THEN 1 END) Adhoc_Trip_Count  FROM (
           SELECT DISTINCT a.allocationId, allocationType FROM escort_allocation a 
           INNER JOIN cab_allocation c ON a.allocationId = c.allocationId 
           INNER JOIN trip_details TD ON a.allocationId = TD.allocationId 
           GROUP BY a.allocationId
        )Z;

<强> OR

SELECT Escort_Count,Adhoc_Trip_Count,Adhoc_Trip_Count+Escort_Count TOTAL FROM(
            SELECT COUNT(DISTINCT Z.allocationId) Escort_Count,SUM(CASE WHEN allocationType='Adhoc Trip' THEN 1 END) Adhoc_Trip_Count,COUNT(D)  FROM (
               SELECT DISTINCT a.allocationId, allocationType,SUM(1) D FROM escort_allocation a 
               INNER JOIN cab_allocation c ON a.allocationId = c.allocationId 
               INNER JOIN trip_details TD ON a.allocationId = TD.allocationId 
               GROUP BY a.allocationId
            )Z
        )ZZ;

您可以尝试以上查询。

绝对会帮助你。

Answer 3

这是你想要的吗？

SELECT td.tripId, COUNT(*) as total, SUM(ea.allocationType = 'Adhoc Trip') as adhocs
FROM trip_details td JOIN
     escort_allocation ea
     ON td.allocationId = ea.allocationId 
GROUP BY td.tripId;

如何在mysql中编写子查询

3 个答案: