Select 不存在的日期 yyyy/mm

Question

我有一个 SQL 查询如下：

SELECT 
    R.BOOK_YM, COUNT(*) 
FROM  
    #TB_TRANSED_GUI_AMOUNT AS R
GROUP 
    BY R.BOOK_YM

选中的结果如下：

BOOK_YM  | count(*)  
---------+---------
201411   | 51 
201412   | 142 
201501   | 1 
201506   | 1

如何修改结果如下：

BOOK_YM | count(*)    
--------+-----------
201411  | 51 
201412  | 142 
201501  | 1 
201502  | 0 
201503  | 0 
201504  | 0 
201505  | 0 
201506  | 1

Answer 1

您可以使用以下方法获取 2 个日期之间所有 YYYYMM 的 table，并在连接中使用生成的 @YMList 变量：

declare @StartDate date = cast(dateadd(month, -12, GetDate()) as date)
declare @EndDate date = cast(GetDate() as date)
declare @YMList TABLE (YYYYMM INT)

;with dates as (
    SELECT cast(@StartDate as Date) [date]
    UNION ALL
    SELECT DATEADD(month,1,t.date)
    FROM dates t
    WHERE t.[date] < @EndDate
)
insert @YMList (YYYYMM)
select 
    YEAR([Date]) * 100 + MONTH([Date]) AS YYYYMM
from dates
WHERE [Date] < @EndDate
OPTION (MAXRECURSION 10000)

Answer 2

试试这个：（我认为 BOOK_YM 是一个 varchar 字段如果不是 CAST 它）

SELECT
    Y.YYYY + M.MM AS BOOK_YM, 
    COUNT(R.BOOK_YM) AS CNT
FROM
    (SELECT SUBSTRING(BOOK_YM, 1, 4) As YYYY
     FROM t
     GROUP BY SUBSTRING(BOOK_YM, 1, 4)) AS Y
    CROSS JOIN
    (SELECT '01' As MM
     UNION ALL SELECT '02'
     UNION ALL SELECT '03'
     UNION ALL SELECT '04'
     UNION ALL SELECT '05'
     UNION ALL SELECT '06'
     UNION ALL SELECT '07'
     UNION ALL SELECT '08'
     UNION ALL SELECT '09'
     UNION ALL SELECT '10'
     UNION ALL SELECT '11'
     UNION ALL SELECT '12') AS M
    LEFT JOIN
    t AS R
    ON Y.YYYY + M.MM = R.BOOK_YM
WHERE 
    Y.YYYY + M.MM BETWEEN (SELECT MIN(BOOK_YM) FROM t) AND (SELECT MAX(BOOK_YM) FROM t)
GROUP BY 
    Y.YYYY + M.MM

Select 不存在的日期 yyyy/mm

Select unexist date yyyy/mm

sql

tsql

stored-procedures