将另一个组添加到递归CTE中

Question

回顾这个SO post

如果存在分组类别“类别”，为了简单起见，可以是X或Y--修改此脚本是否是一个微不足道的事情，以便它会为每个类别添加缺少的日期？

我认为该类别需要加入CTE？

换句话说，如果我有以下初始表：

...我如何进行以下操作：

将很快上传我的尝试

我称之为初始表#x。我希望调整如下所示的递归CTE查询以包含字段Category：

DECLARE @MinDate DATETIME; 
SET @MinDate =  (SELECT Min(DATE) FROM #x)

DECLARE @MaxDate DATETIME; 
SET @MaxDate =  (SELECT Max(DATE) FROM #x)

;WITH times AS 
    ( 
    SELECT @MinDate dt , 1 depth 
    UNION ALL 
    SELECT 
            DATEADD(d, depth, @MinDate) dt 
            , 1 + depth as depth 
    FROM times 
    WHERE DATEADD(d, depth, @MinDate) <= @MaxDate
    ) 
SELECT 
    * 
FROM 
    TIMES t
    LEFT OUTER JOIN #X x
        ON 
        t.dt = x.Date

好的 - 我已经绑定了一个CROSS JOIN，但它错误地扩展了事情：

SELECT DISTINCT Category INTO #Cat FROM #x

DECLARE @MinDate DATETIME; 
SET @MinDate =  (SELECT Min(DATE) FROM #x)

DECLARE @MaxDate DATETIME; 
SET @MaxDate =  (SELECT Max(DATE) FROM #x)


;WITH times AS 
    ( 
    SELECT 
            Category
            , @MinDate dt 
            , 1 depth 
    FROM #Cat
    UNION ALL 
    SELECT 
            c.Category
            , DATEADD(d, depth, @MinDate) dt 
            , 1 + depth as depth 
    FROM 
            times t
            CROSS JOIN #Cat c
                --ON c.Category IS NOT NULL
    WHERE DATEADD(d, depth, @MinDate) <= @MaxDate
    ) 
SELECT 
    * 
FROM 
    TIMES

这似乎运作正常：

SELECT DISTINCT Category INTO #Cat FROM #x

DECLARE @MinDate DATETIME; 
SET @MinDate =  (SELECT Min(DATE) FROM #x)

DECLARE @MaxDate DATETIME; 
SET @MaxDate =  (SELECT Max(DATE) FROM #x)


;WITH times AS 
    ( 
    SELECT 
            Category
            , @MinDate dt 
            , 1 depth 
    FROM #Cat
    UNION ALL 
    SELECT 
            Category
            , DATEADD(d, depth, @MinDate) dt 
            , 1 + depth as depth 
    FROM 
            times t
    WHERE DATEADD(d, depth, @MinDate) <= @MaxDate
    ) 
SELECT 
    * 
FROM 
    TIMES

Answer 1

这样的事情可以解决问题：

declare @curDate datetime, @maxDate datetime
declare @count tinyint

select @curDate = convert(datetime, '20120101', 112), @maxDate = getdate()
select @count = 0

while @curDate < @maxDate
begin
  select @count = count(1) from tablename where Category = 'X' and convert(varchar(8), Date, 112) = convert(varchar(8), @curDate, 112)

  if @count > 0
  begin
    insert into tablename
    select 'X', @curDate, 0
  end

  select @curDate = dateadd(dd, 1, @curDate)
end

Answer 2

这是一个没有日历表的解决方案（这是生产中必须的）。您可能在变量中有日期范围，或者您可以从the_table获取min（）和max（）。

编辑：将类别纳入日期范围生成的较短版本

declare @startdate datetime = '2012-1-1'
declare @enddate datetime = '2012-1-5'

; with dates([date], category) as (
  select distinct @startdate, category
    from the_table
   union all
  select dateadd (day, 1, [date]), category
    from dates
   where [date] < @enddate
)
select dates.date, 
       dates.category, 
       isnull(the_table.amount, 0) Amount
  from dates
  left join the_table
    on dates.date = the_table.date
   and dates.category = the_table.category
 order by dates.category, dates.date
option (maxrecursion 0)

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