sql函数里判断后输出“/”

[fayxue]

create function split(@sql varchar(500),@n int)
returns varchar(100)
as
begin
set @sql=@sql+','
declare @return varchar(100),@i int,@var varchar(500)
set @i=0
while(charindex(',',@sql)>0)
begin
set @var=isnull(@var+ case @i when 3 then '|' else ',' end,'')+left(@sql,charindex(',',@sql)-1)
set @sql=right(@sql,len(@sql)-charindex(',',@sql))
set @i=case @i when 3 then 0 else @i end +1
end
set @var=@var+'|'
while(charindex('|',@var)>0)
begin
set @return=isnull(@return+',','') + parsename(replace(left(@var,charindex('|',@var)-1),',','.'),case @n when 1 then 3 when 2 then 2 when 3 then 1 end)
set @var=right(@var,len(@var)-charindex('|',@var))
end
return @return
end

select dbo.split('DN,出发日期不可变更,none,TO,可签转,none,RO,可退票,none,RN,不可退票,none',1)
select dbo.split('DN,出发日期不可变更,none,TO,可签转,none,RO,可退票,none,RN,不可退票,none',2)
select dbo.split('DN,出发日期不可变更,none,TO,可签转,none,RO,可退票,none,RN,不可退票,none',3)
加上个判断 如果输入为空则输出"/"
比如select dbo.split("",1)结果是"/"
select dbo.split("",2)结果是"/"
select dbo.split("",3)结果是"/"
T-SQL语句该怎么加？

[中国风]

create function split(@sql varchar(500),@n int)
returns varchar(100)
as
begin
    set @sql=@sql+','
    declare @return varchar(100),@i int,@var varchar(500)
    set @i=0
    while(charindex(',',@sql)>0)
    begin
        set @var=isnull(@var+ case @i when 3 then ' ¦' else ',' end,'')+left(@sql,charindex(',',@sql)-1)
        set @sql=right(@sql,len(@sql)-charindex(',',@sql))
        set @i=case @i when 3 then 0 else @i end +1
    end
    set @var=@var+' ¦'
    while(charindex(' ¦',@var)>0)
    begin
        set @return=isnull(@return+',','') + parsename(replace(left(@var,charindex(' ¦',@var)-1),',','.'),case @n when 1 then 3 when 2 then 2 when 3 then 1 end)
        set @var=right(@var,len(@var)-charindex(' ¦',@var))
    end
    return coalesce(nullif(@return,''),'/')--改
end

[utpcb]

楼上那个可以

[ojuju10]

create function split(@sql varchar(500),@n int) 
returns varchar(100) 
as 
begin 
    set @sql=@sql+',' 
    declare @return varchar(100),@i int,@var varchar(500) 
    set @i=0 
    while(charindex(',',@sql)>0) 
    begin 
        set @var=isnull(@var+ case @i when 3 then ' ¦' else ',' end,'')+left(@sql,charindex(',',@sql)-1) 
        set @sql=right(@sql,len(@sql)-charindex(',',@sql)) 
        set @i=case @i when 3 then 0 else @i end +1 
    end 
    set @var=@var+' ¦' 
    while(charindex(' ¦',@var)>0) 
    begin 
        set @return=isnull(@return+',','') + parsename(replace(left(@var,charindex(' ¦',@var)-1),',','.'),case @n when 1 then 3 when 2 then 2 when 3 then 1 end) 
        set @var=right(@var,len(@var)-charindex(' ¦',@var)) 
    end 
if charindex('/',@return)>0
set @return=left(@return,len(@return)-1)
    
return @return 
end 

[fayxue]

同样也很感谢3楼啊 非常感谢