Question

String = '45,12,37,89,10,107,64,97'

创建一个以逗号分隔值的过程，我们可以说数字数组并查找最大值。

Answer 1

您可以执行以下操作。

创建一个提取数据的函数

CREATE FUNCTION [dbo].[fnSplitString]
(
      @str as varchar(max),
      @delimiter as varchar(1)
)
RETURNS @TableReturn table(ID integer)
AS
BEGIN
    IF (@str IS NULL or @str ='')
        BEGIN
              INSERT INTO @TableReturn SELECT 0
        END
    ELSE
        WHILE (charindex(@delimiter,@str)>0)
        BEGIN
            INSERT INTO @TableReturn
            SELECT SUBSTRING (@str,1,charindex(@delimiter,@str)-1)
            SET @str = SUBSTRING (@str,charindex(@delimiter,@str)+1, len(@str))
        END
        IF (@str <> '' and @str <> ',' )
        BEGIN
            INSERT INTO @TableReturn SELECT @str
        END
    RETURN 
END

然后叫它：

SELECT TOP(1)* FROM dbo.fnSplitString('45,12,37,89,10,107,64,97', ',') ORDER BY ID DESC

否则：

SELECT MAX(ID) FROM dbo.fnSplitString('45,12,37,89,10,107,64,97', ',')

Answer 2

我将此方法加入书签。不记得来源，但它就像魅力一样。已为您修改过。试试：

Create table #Testdata(Data varchar(max))
Insert #Testdata select '45,12,37,89,10,107,64'


;with tmp(DataItem, Data) as (
select LEFT(Data, CHARINDEX(',',Data+',')-1),
       STUFF(Data, 1, CHARINDEX(',',Data+','), '')
from #Testdata
union all
select LEFT(Data, CHARINDEX(',',Data+',')-1),
       STUFF(Data, 1, CHARINDEX(',',Data+','), '')
from tmp
where Data > ''
)
select  max(cast(DataItem as int))
from tmp
OPTION (maxrecursion 0)

通过在存储过程中将逗号分隔的整数作为字符串传递来查找最大值

2 个答案: