如何將同一表中不同條件的每個計數值分組為1個表

Question

我有1個內部聯接表

SELECT COUNT(*) as dirtyRoom FROM t_room INNER JOIN t_room_type ON t_room.roomType = t_room_type.code WHERE status = 'sPVDirty'   output :  dirtyRoom : 13


SELECT COUNT(*) as readyRoom FROM t_room INNER JOIN t_room_type ON t_room.roomType = t_room_type.code WHERE status = 'sPVReady'   output : readyRoom : 33

SELECT COUNT(*) as maintenanceRoom FROM t_room INNER JOIN t_room_type ON t_room.roomType = t_room_type.code WHERE status = 'sPVMaint' output : maintenanceRoom : 4

我想將不同條件的每個計數值分組到1個表中，並在3列中顯示每個值

輸出：表1

 dirtyRoom             readyRoom           maintenanceRoom
    13                     33                     4   

怎么做？

Answer 1

嘗試這個

SELECT COUNT(IF(status='sPVDirty',status,0)) As DirtyRoom,
       COUNT(IF(status='sPVReady',status,0)) As ReadyRoom,
       COUNT(IF(status='sPVMaint',status,0)) As MaintenanceRoom 
FROM t_room INNER JOIN t_room_type ON t_room.roomType = t_room_type.code

要么：

SELECT SUM(IF(status='sPVDirty',1,0)) As DirtyRoom,
       SUM(IF(status='sPVReady',1,0)) As ReadyRoom,
       SUM(IF(status='sPVMaint',1,0)) As MaintenanceRoom 
FROM t_room INNER JOIN t_room_type ON t_room.roomType = t_room_type.code

所以你的輸出將是

+------------+------------+--------------------+
| DirtyRoom  | ReadyRoom  |MaintenanceRoom     |
+------------+------------+--------------------+
| 13         | 33         |4                   |
+------------+------------+--------------------+

Answer 2

嘗試

SELECT 
    IF(status = 'sPVDirty', count(status), 0) as dirtyRoom,
    IF(status = 'sPVReady', count(status), 0) as readyRoom,
    IF(status = 'sPVMaint', count(status), 0) as maintenanceRoom,
FROM t_room INNER JOIN t_room_type ON t_room.roomType = t_room_type.code