我有一个查询:
SELECT availables.bookdate AS Date, DATEDIFF(now(),availables.updated_at) as Age
FROM availables
INNER JOIN rooms
ON availables.room_id=rooms.id
WHERE availables.bookdate BETWEEN '2009-06-25' AND date_add('2009-06-25', INTERVAL 4 DAY) AND rooms.hostel_id = 5094
GROUP BY availables.bookdate
返回类似的内容:
Date Age
2009-06-25 0
2009-06-26 2
2009-06-27 1
2009-06-28 0
2009-06-29 0
我怎样才能对返回的行数进行计数..(在本例中为5)和年龄的和?要使用Count和SUM返回一行吗?
Count SUM
5 3
由于
答案 0 :(得分:36)
通常,您可以将Query的结果(基本上是一个表)作为FROM子句源插入 另一个查询,所以会写这样的东西:
SELECT COUNT(*), SUM(SUBQUERY.AGE) from
(
SELECT availables.bookdate AS Date, DATEDIFF(now(),availables.updated_at) as Age
FROM availables
INNER JOIN rooms
ON availables.room_id=rooms.id
WHERE availables.bookdate BETWEEN '2009-06-25' AND date_add('2009-06-25', INTERVAL 4 DAY) AND rooms.hostel_id = 5094
GROUP BY availables.bookdate
) AS SUBQUERY
答案 1 :(得分:7)
您只需将查询包装在另一个中:
SELECT COUNT(*), SUM(Age)
FROM (
SELECT availables.bookdate AS Count, DATEDIFF(now(),availables.updated_at) as Age
FROM availables
INNER JOIN rooms
ON availables.room_id=rooms.id
WHERE availables.bookdate BETWEEN '2009-06-25' AND date_add('2009-06-25', INTERVAL 4 DAY) AND rooms.hostel_id = 5094
GROUP BY availables.bookdate
) AS tmp;
答案 2 :(得分:1)
我不知道你是否需要包装它。这不会起作用吗?
SELECT COUNT(*), SUM(DATEDIFF(now(),availables.updated_at))
FROM availables
INNER JOIN rooms ON availables.room_id=rooms.id
WHERE availables.bookdate BETWEEN '2009-06-25'
AND date_add('2009-06-25', INTERVAL 4 DAY)
AND rooms.hostel_id = 5094
GROUP BY availables.bookdate);
如果你的目标是返回两个结果集,那么你需要暂时存储它。
答案 3 :(得分:0)
请注意,您的初始查询可能无法返回您想要的内容:
SELECT availables.bookdate AS Date, DATEDIFF(now(),availables.updated_at) as Age
FROM availables INNER JOIN rooms ON availables.room_id=rooms.id
WHERE availables.bookdate BETWEEN '2009-06-25' AND date_add('2009-06-25', INTERVAL 4 DAY) AND rooms.hostel_id = 5094 GROUP BY availables.bookdate
您按照图书日期进行分组,但您没有在查询的第二列上使用任何分组功能。
您可能正在寻找的查询是:
SELECT availables.bookdate AS Date, count(*) as subtotal, sum(DATEDIFF(now(),availables.updated_at) as Age)
FROM availables INNER JOIN rooms ON availables.room_id=rooms.id
WHERE availables.bookdate BETWEEN '2009-06-25' AND date_add('2009-06-25', INTERVAL 4 DAY) AND rooms.hostel_id = 5094
GROUP BY availables.bookdate