按分组字段排列的大查询顺序

Question

我有一个按日期分组的查询，效果很好。

SELECT EXTRACT(date FROM DATETIME(timestamp, 'US/Eastern')) date, SUM(users) total_users FROM `mydataset.mytable` 
GROUP BY EXTRACT(date FROM DATETIME(timestamp, 'US/Eastern'))

但是当我尝试按日期订购时：

SELECT EXTRACT(date FROM DATETIME(timestamp, 'US/Eastern')) date, SUM(users) total_users FROM `mydataset.mytable` 
GROUP BY EXTRACT(date FROM DATETIME(timestamp, 'US/Eastern'))
ORDER BY EXTRACT(date FROM DATETIME(timestamp, 'US/Eastern'));

我收到以下错误：

SELECT list expression references column timestamp which is neither grouped nor aggregated at [1:35]

时间戳列显然是分组的一部分，更奇怪的是，它没有ORDER BY子句即可工作......这是怎么回事？

Answer 1

#standardSQL
SELECT 
EXTRACT(DATE FROM DATETIME(timestamp, 'US/Eastern')) date, 
SUM(users) total_users 
FROM `mydataset.mytable` 
GROUP BY 1
ORDER BY 1 

Answer 2

您可以尝试子选择：

#standardSQL
SELECT
date,
total_users
FROM (
SELECT
EXTRACT(date FROM DATETIME(timestamp,'US/Eastern')) date,
SUM(users) total_users
FROM
`mydataset.mytable`
GROUP BY EXTRACT(date FROM DATETIME(timestamp, 'US/Eastern'))
)
ORDER BY
date