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我正在寻找一种解决方案，我可以在两个日期生成每周范围，其中每周范围将基于星期几。
例子：

date1 = 2011-12-17 date2 = 2012-05-16

结果：

week1 2011-12-17 to 2011-12-17 -- since it the first date false on a saturday
week2 2011-12-18 to 2011-12-24
...
last week 2012-05-13 to 2012-05-16

我已经在 PostgreSQL 中编写了我的 SQL：

SELECT
    time_series.cur
    ,case (6 - date_part('dow', cur)::int) = 0
    when true then cur
       else case time_series.cur + (6 - date_part('dow',cur)::int) < current_date
          when true then time_series.cur + (6 - date_part('dow', cur)::int)
          else current_date
          end
       end
    as nxt
FROM
    (select generate_series(current_date - 151
                          , current_date, '1 day')::date AS cur) time_series
where cur < current_date
and   case (current_date - 151 != cur and cur != current_date)
         when true then date_part('dow', cur)::int = 0
         else true
       end

有没有更清洁的方法来做到这一点？

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1 回答 1

2

这似乎更干净（而且更快）：

WITH x AS (
    SELECT '2011-12-17'::date AS my_start
         , '2012-05-16'::date As my_end
    )
SELECT GREATEST(d1, my_start) AS d1
      ,LEAST(d1 + 6, my_end)  AS d2
FROM  (
    SELECT generate_series(date_trunc('week', my_start + 1)
                         , date_trunc('week', my_end + 1)
                         , '1 week')::date - 1 AS d1
    FROM x
    ) d, x

就像我在回答您之前的问题时所解释的那样，只是这一次是从星期日到星期六。

于 2012-05-16T11:41:14.117 回答