Question

如果此查询返回的日期在请求的范围内。

select created_at from user where created_at between '2015-01-06 00:00:00.000000' and '2015-03-06 00:00:00.000000'

有没有一种方法可以得到这样的结果，但是有多个日期包含在一个日期数组中。

我只是想举一个例子。我有这个日期数组，总是会有第一个和最后一个日期。

Array['2015-01-06 00:00:00.000000','2015-02-10 15:17:18.895000' <- First range
      '2017-10-05 14:41:04.191000','2017-10-11 14:49:36.454000' <- Second range

有没有办法放置这样的脚本？

select created_at from win_users 
where (created_at between [First Date] and [Second Date])
or (created_at between [Third Date] and [Fourth Date])

但是不使用循环来连接where语句吗？

Answer 1

在这种情况下，日期数组非常不舒服。使用daterange和containtment operator <@的数组，例如：

with my_table(id, created_at) as (
values 
    (1, '2015-01-10'::timestamp),
    (2, '2016-05-10'),
    (3, '2017-10-10')
)

select *
from my_table
where created_at::date <@ any(array[daterange('2015-01-06','2015-02-10'), daterange('2017-10-05','2017-10-11')])

 id |     created_at      
----+---------------------
  1 | 2015-01-10 00:00:00
  3 | 2017-10-10 00:00:00
(2 rows)

如果您绝对要使用日期数组（坦白地说，我不这么认为），请使用此函数将其转换为daterange数组：

create or replace function date_pairs_to_ranges(date[])
returns daterange[] language sql as $$
    select array_agg(daterange(d1, d2))
    from unnest($1) with ordinality as u1(d1, o1)
    join unnest($1) with ordinality as u2(d2, o2)
    on o1/ 2* 2 < o1 and o2 = o1+ 1
$$;

with my_table(id, created_at) as (
values 
    (1, '2015-01-10'::timestamp),
    (2, '2016-05-10'),
    (3, '2017-10-10')
)

select *
from my_table
where created_at::date <@ any(date_pairs_to_ranges(array['2015-01-06','2015-02-10','2017-10-05','2017-10-11']::date[]))

Answer 2

如果范围数组始终采用您发布的格式（即4个项目，前两个元素是第一个范围，后两个元素是第二个范围），则可以编写如下查询：

WITH ranges AS (
    SELECT '{2015-01-06 00:00:00.000000,2015-02-10 15:17:18.895000,2017-10-05 14:41:04.191000,2017-10-11 14:49:36.454000}'::date[] dates
)
    SELECT win_users.created_at FROM win_users, ranges
        WHERE (win_users.created_at > ranges.dates[1] AND win_users.created_at < ranges.dates[2]) OR (win_users.created_at > ranges.dates[3] AND win_users.created_at < ranges.dates[4]);

PostgreSQL从日期范围之间的日期范围中选择

2 个答案: