从位掩码确定星期几

Question

我正在使用第三方应用程序并尝试根据数据提取有关班次信息的有意义的信息。

shift_pattern_start_dt     pattern
2014-05-27                 1111000
2015-10-25                 1110011

2014-05-27是一个Tuesday模式的起始位置是Tuesday。所以我希望结果显示 Tuesday、Wednesday、Thursday 和 Friday.

2015-10-25是一个Sunday这个模式的起始位置是Sunday。结果应为 Sunday、Monday、Tuesday、Friday 和 Saturday。

对于确定正确的工作日有什么想法或建议吗？

Answer 1

Declare @YourTable table (shift_pattern_start_dt date, pattern varchar(25))
Insert Into @YourTable values
('2014-05-27','1111000'),
('2015-10-25','1110011')

Select *
      ,NewCol = concat(
                IIF(substring(pattern,1,1)='1',   +DateName(WEEKDAY,shift_pattern_start_dt),'')
               ,IIF(substring(pattern,2,1)='1',','+DateName(WEEKDAY,dateadd(DAY,1,shift_pattern_start_dt)),null)
               ,IIF(substring(pattern,3,1)='1',','+DateName(WEEKDAY,dateadd(DAY,2,shift_pattern_start_dt)),null)
               ,IIF(substring(pattern,4,1)='1',','+DateName(WEEKDAY,dateadd(DAY,3,shift_pattern_start_dt)),null)
               ,IIF(substring(pattern,5,1)='1',','+DateName(WEEKDAY,dateadd(DAY,4,shift_pattern_start_dt)),null)
               ,IIF(substring(pattern,6,1)='1',','+DateName(WEEKDAY,dateadd(DAY,5,shift_pattern_start_dt)),null)
               ,IIF(substring(pattern,7,1)='1',','+DateName(WEEKDAY,dateadd(DAY,6,shift_pattern_start_dt)),null)
               )
 From  @YourTable

Returns

shift_pattern_start_dt  pattern   NewCol
2014-05-27              1111000   Tuesday,Wednesday,Thursday,Friday
2015-10-25              1110011   Sunday,Monday,Tuesday,Friday,Saturday

EDIT - Cross Apply Version

Select A.*
      ,B.*
 From  @YourTable A
 Cross Apply (
                Select NewCol =Stuff((Select ',' +D 
                  From (
                        Select N,D = IIF(substring(A.pattern,N,1)='0',null,DateName(WEEKDAY,DateAdd(DAY,N-1,A.shift_pattern_start_dt)))
                         From (Values (1),(2),(3),(4),(5),(6),(7)) N(N)             
                        ) B1 
                  For XML Path ('')),1,1,'') 
             ) B

Execution Plan for Concat() Approach

Execution Plan for Cross Apply Approach

从位掩码确定星期几

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