我在使用这个查询时遇到了一些问题,看来我不能在分组查询中使用别名作为引用
SELECT v.V_VEHICLEID, v.V_LICENSENO,
ROUND((MAX(IF(DAY(WP_DATETIME) = 1, WP_ODOMETER, NULL)) - MIN(IF(DAY(WP_DATETIME) = 1, WP_ODOMETER, NULL))) / 1000) AS TRIP1,
...,
ROUND((MAX(IF(DAY(WP_DATETIME) = 31, WP_ODOMETER, NULL)) - MIN(IF(DAY(WP_DATETIME) = 31, WP_ODOMETER, NULL))) / 1000) AS TRIP31,
ROUND(MAX(IF(DAY(WP_DATETIME) = 1, WP_FUELREAD, NULL)) - MIN(IF(DAY(WP_DATETIME) = 1, WP_FUELREAD, NULL)),2) AS FUEL1,
...,
ROUND(MAX(IF(DAY(WP_DATETIME) = 31, WP_FUELREAD, NULL)) - MIN(IF(DAY(WP_DATETIME) = 31, WP_FUELREAD, NULL)),2) AS FUEL31,
(SELECT TRIP1 / FUEL1) AS ECON1,
...,
(SELECT TRIP31 / FUEL31) AS ECON31
FROM VEHICLES v
JOIN WAYPOINTS wp on wp.WP_VEHICLEID = v.V_VEHICLEID
WHERE MONTH(wp.WP_DATETIME) = '6' AND v.V_USER = 'tc'
GROUP BY wp.WP_VEHICLEID
错误
Reference 'TRIP1' not supported (reference to group function)
有什么解决办法吗?
最佳答案
您不能在同一查询中使用您在查询中定义的列别名。尝试如下操作:
SELECT *,
TRIP1 / FUEL1 AS ECON1,
TRIP31 / FUEL31 AS ECON31,
OTHER COLUMNS....
FROM
(
SELECT v.V_VEHICLEID,
v.V_LICENSENO,
ROUND((MAX(IF(DAY(WP_DATETIME) = 1, WP_ODOMETER, NULL)) - MIN(IF(DAY(WP_DATETIME) = 1, WP_ODOMETER, NULL))) / 1000) AS TRIP1,
ROUND(MAX(IF(DAY(WP_DATETIME) = 1, WP_FUELREAD, NULL)) - MIN(IF(DAY(WP_DATETIME) = 1, WP_FUELREAD, NULL)),2) AS FUEL1,
ROUND((MAX(IF(DAY(WP_DATETIME) = 31, WP_ODOMETER, NULL)) - MIN(IF(DAY(WP_DATETIME) = 31, WP_ODOMETER, NULL))) / 1000) AS TRIP31,
ROUND(MAX(IF(DAY(WP_DATETIME) = 31, WP_FUELREAD, NULL)) - MIN(IF(DAY(WP_DATETIME) = 31, WP_FUELREAD, NULL)),2) AS FUEL31,
OTHER COLUMNS...
FROM VEHICLES v
JOIN WAYPOINTS wp
ON wp.WP_VEHICLEID = v.V_VEHICLEID
WHERE MONTH(wp.WP_DATETIME) = '6'
AND v.V_USER = 'tc'
GROUP BY wp.WP_VEHICLEID
) t
关于mysql - 群组功能不支持引用,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/6532788/