拆分字符串为单一字符

如下面这个样子：

 

本函式是学习使用WHILE以及SUBSTRING的应用：

 

CREATE FUNCTION [dbo].[svf_SplitStringToSingleCharacter](
  @DataSource NVARCHAR(4000)
)
RETURNS NVARCHAR(4000)
AS
BEGIN
   DECLARE @rtvResult NVARCHAR(4000),@length INT       

   SET @length = lEN(ISNULL(@DataSource,'')) 
   
   IF @length = 0
      SET @rtvResult = N''
   ELSE
   BEGIN
        WHILE @length > 0
        BEGIN
            SET @rtvResult = ISNULL(@rtvResult + ',',N'') + '''' + SUBSTRING(@DataSource,@length,1) + ''''
            SET @length = @length - 1
        END
   END
     
   RETURN @rtvResult
END

Source Code