Question

我想创建一个临时表，在其中指定开始和结束日期（标价）。然后结果是一列中的日期和另一列中的每天的小时。

它看起来像这样：

date       hour
------------------
1/17/19     1
1/17/19     2
1/17/19     3
   .        .
   .        .
1/17/19    24
1/18/19     1
1/18/19     2
1/18/19     3
   .        .
   .        .
   .        .

所以看来我想在小时内使用generate_series。但不确定如何将日期与日期匹配。

这不是为我完成的事情：

WITH hrs AS (SELECT * FROM generate_series(1,24)),
pricedate AS (SELECT * FROM generate_series('2018-01-24', '2018-01-26', interval '1 day'))


SELECT pricedate, hrs
WHERE pricedate BETWEEN '2018-01-24' AND '2018-01-26'
ORDER BY pricedate, hour

Answer 1

使用cross join：

WITH hrs AS (
       SELECT gs.hr
       FROM generate_series(1,24) gs(hr)
      ),
      pricedate AS (
       SELECT gs.priceate
       FROM generate_series('2018-01-24', '2018-01-26', interval '1 day') gs(pricedate)
      )
SELECT pricedate.pricedate, hrs.hr
FROM hrs CROSS JOIN pricedate
WHERE pricedate.pricedate BETWEEN '2018-01-24' AND '2018-01-26'
ORDER BY pricedate.pricedate, hrs.hour

Answer 2

select d::date as date, extract(hour from d)::int+ 1 as hour
from generate_series('2018-01-24', '2018-01-26 23:00', interval '1 hour') s(d)

    date    | hour 
------------+------
 2018-01-24 |    1
 2018-01-24 |    2
 2018-01-24 |    3
 2018-01-24 |    4
...

从日期范围创建日期和小时列

2 个答案: