如何查看在SQL中当前选择后表中是否重新出现该值

Question

我有下面的数据表CRA_feasibility_test

atmid       CRA     monday  tuesday wednesday   thursday    friday  saturday
DA0068C1    ABC       Y      N      Y           N           N        Y

我想根据我的date.If的工作日来选择数据，它是Y，然后想得到最近的'Y‘，也就是从@date中选择Y的那一天。

我也想要下一个

我正在做以下工作

declare @date datetime set @date ='2018-06-15' 
Select  @dateT as indentdate, DATENAME(dw,@dateT) as weekdayname,

          case when DATENAME(dw,@dateT)  ='monday'        
                                                 then  monday

                  when DATENAME(dw,@dateT)  ='tuesday'           then  
                                                            tuesday
                  when DATENAME(dw,@dateT)  ='wednesday'      then  
                                                         wednesday
                  when DATENAME(dw,@dateT)  ='Thursday'         then  
                                                       thursday
                 when DATENAME(dw,@dateT)  ='Friday'               then  
                                                   friday
                 when DATENAME(dw,@dateT)  ='Saturday'           then  
                                                 saturday       


end   feasible
from [CRA_feasibility_test] 

Answer 1

如果我正确理解，您可以尝试通过cte recursive为接下来的7天创建一个日历表，然后使用CROSS APPLY和values make Unp透视来获取Y日期，这是最近的一天。

declare @dateT datetime
set @dateT ='2018-06-15'

;with calendar as (
  select @dateT startDt,dateadd(day,7,@dateT) endDt, 1 rn
  union all
  select dateadd(day,1,startDt) , endDt,rn +1
  from calendar
  WHERE  dateadd(day,1,startDt)<endDt
), cte as (
select 
        atmid,v.*
from CRA_feasibility_test cross apply (
    values ('monday',monday), ('tuesday',tuesday), ('wednesday',wednesday), ('thursday',thursday), ('friday',friday), ('saturday',saturday)
) v(name,flag)

)


select atmid,
    @dateT today,
    min(case when flag = 'Y' then startDt end) nextYDay,
    datename(dw,min(case when flag = 'Y' then startDt end) ) nextYname
from calendar t1 
join cte t2 on datename(dw,startDt) = t2.name
group by atmid

木琴

结果

atmid       today               nextYDay            nextYname
DA0068C1    15/06/2018 00:00:00 16/06/2018 00:00:00 Saturday