对于两个日期之间的每个季度，在 SQL SERVER 中逐季度添加行

Question

我有一个表格，类型为 int、datetime、datetime：

id    start date    end date
--    ----------    ----------
1     2019-04-02    2020-09-17
2     2019-08-10    2020-08-10

这里是创建/插入：

CREATE TABLE dbo.something
(
  id           int, 
  [start date] datetime, 
  [end date]   datetime
);

INSERT dbo.something(id,[start date],[end date]) 
  VALUES(1,'20190402','20200917'),(2,'20190810','20200810');

什么是可以产生这些结果的 SQL 查询：

id    Year    Quarter
--    ----    ----------
1     2019    2
1     2019    3
1     2019    4
1     2020    1
1     2020    2
1     2020    3
2     2019    3
2     2019    4
2     2020    1
2     2020    2
2     2020    3

Answer 1

只需使用递归 CTE。此版本从第 0 年切换到计算季度：

with cte as (
      select id, 
             year(start_date) * 4 +  datepart(quarter, start_date) - 1 as yyyyq,
             year(end_date) * 4 + datepart(quarter, end_date) - 1 as end_yyyyq
      from t
      union all
      select id, yyyyq + 1, end_yyyyq
      from cte
      where yyyyq < end_yyyyq
     )
select id, yyyyq / 4 as year, (yyyyq % 4) + 1 as quarter
from cte;

Here 是一个 dbfiddle。

Answer 2

如果您无法制作另一个参考表/等，您可以使用 DATEDIFF（和 DATEPART）使用季度，然后使用一些简单的日期算术。

下面的逻辑只是为了找到每个开始日期的第一季度，然后再找到其他季度的数量以达到最大值。然后执行 SELECT，将其他季度添加到开始日期，以获取每个季度。

查询中最难理解 imo 的部分是 WITH numberlist 部分 - 所有这些都是生成一系列介于 0 和最大四分之一差数之间的整数。如果您已经有一个数字表，则可以使用它。

关键代码部分如下，这是完整的DB_Fiddle 以及一些额外的测试数据。

CREATE TABLE #yourtable (id int, startdate date, enddate date)
INSERT INTO #yourtable (id, startdate, enddate) VALUES
(1, '2019-04-02', '2020-09-17'),
(2, '2019-08-10', '2020-08-20')

; WITH number_list AS
        -- list of ints from 0 to maximum number of quarters
        (SELECT n 
            FROM (SELECT ones.n + 10*tens.n AS n
                    FROM (VALUES(0),(1),(2),(3),(4),(5),(6),(7),(8),(9)) ones(n),
                         (VALUES(0),(1),(2),(3),(4),(5),(6),(7),(8),(9)) tens(n)
                ) AS a
            WHERE n <= (SELECT MAX(DATEDIFF(quarter,startdate,enddate)) FROM #yourtable)
        )
    SELECT  id,
            YEAR(DATEADD(quarter, number_list.n, startdate)) AS [Year],
            DATEPART(quarter, DATEADD(quarter, number_list.n, startdate)) AS [Quarter]
    FROM    (SELECT id, startdate, DATEDIFF(quarter,startdate,enddate) AS num_additional_quarters FROM #yourtable) yt
            CROSS JOIN number_list
    WHERE   number_list.n <= yt.num_additional_quarters 


DROP TABLE #yourtable

Answer 3

首先创建一个包含日期、对应季度和年份的日期维度表。然后使用下面的查询来获得结果。根据您的架构调整列和表名。

with q_date as
(
select 1 as id, '2019-04-02' :: date as start_date, '2020-09-17' :: date as end_date
UNION ALL
select 2 as id, '2019-08-10' :: date as start_date, '2020-08-10' :: date as end_date
)


select qd.id, dd.calendar_year, dd.calendar_quarter_number 
from dim_date dd, q_date qd 
where dd.date_dmk between qd.start_date and qd.end_date
group by qd.id, dd.calendar_year, dd.calendar_quarter_number
order by qd.id, dd.calendar_year, dd.calendar_quarter_number;