更新问题:
ERROR: column "Fruits" does not exist
运行 Postgres 7.4(是的,我们正在升级)
为什么我不能按列别名进行排序?想要 ORDER BY 中的“TypeOfFruits”,为什么?
SELECT (CASE
WHEN tof."TypeOfFruits" = 'A' THEN 'Apple'
WHEN tof."TypeOfFruits" = 'P' THEN 'Pear'
WHEN tof."TypeOfFruits" = 'G' THEN 'Grapes'
ELSE 'Other' END) AS "Fruits",
SUM(CASE WHEN r.order_date
BETWEEN DATE_TRUNC('DAY', LOCALTIMESTAMP) AND DATE_TRUNC('DAY', LOCALTIMESTAMP) + INTERVAL '1 DAY'
THEN 1 ELSE 0 END) AS daily,
SUM(CASE WHEN r.order_date
BETWEEN DATE_TRUNC('MONTH', LOCALTIMESTAMP) AND DATE_TRUNC('MONTH', LOCALTIMESTAMP) + INTERVAL '1 MONTH'
THEN 1 ELSE 0 END) AS monthly,
SUM(CASE WHEN r.order_date
BETWEEN DATE_TRUNC('YEAR', LOCALTIMESTAMP) AND DATE_TRUNC('YEAR', LOCALTIMESTAMP) + INTERVAL '1 YEAR'
THEN 1 ELSE 0 END) AS yearly,
SUM(CASE WHEN r.order_date >= '01-01-2011 00:00:00' THEN 1 ELSE 0 END) AS lifetime
FROM reports AS r, "TypeOfFruits" AS tof
WHERE r.id = tof."ID"
GROUP BY "Fruits"
ORDER BY CASE
WHEN "Fruits" = 'Apple' THEN 1
WHEN "Fruits" = 'Pear' THEN 2
WHEN "Fruits" = 'Grapes' THEN 3
ELSE 4
END
目前的结果
Fruits;daily;monthly;yearly;lifetime
"Apple";17;1174;3136;3136
"Pear";28;94;94;94
"Grapes";0;191;490;490
"Other";0;2;27;27
"Other";0;0;1;1
"Other";0;0;27;27
"Other";0;6;28;28
"Other";0;58;229;229
"Other";0;3;3;3
"Other";0;0;1;1
所需的结果将是“其他”总数的一行,因此总共四行 (x 将是总数)
Fruits;daily;monthly;yearly;lifetime
"Apple";17;1174;3136;3136
"Pear";28;94;94;94
"Grapes";0;191;490;490
"Other";x;x;x;x
最佳答案
您可以使用 ORDER BY 1
按第一个字段“Fruits”排序。这同样适用于 GROUP BY
更新
对于订单,不是在 order by
中执行 case
,而是在……说……第二个位置创建一个新列:
(CASE
WHEN "Fruits" = 'Apple' THEN 1
WHEN "Fruits" = 'Pear' THEN 2
WHEN "Fruits" = 'Grapes' THEN 3
ELSE 4 ) as Order
然后在你的 ORDER BY 2
中。
关于sql - ORDER BY 别名不起作用,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/6458669/