返回@find在@str中第(@n)次出现的位置。没有第(@n)次返回0。

 create function fn_find(@find varchar(8000), @str varchar(8000), @n smallint)

     returns int

 as

 begin

     if @n < 1 return (0)

     declare @start smallint, @count smallint, @index smallint, @len smallint

     set @index = charindex(@find, @str)

     if @index = 0 return (0)

     else select @count = 1, @len = len(@find)

     while @index > 0 and @count < @n

         begin

             set @start = @index + @len

             select @index = charindex(@find, @str, @start), @count = @count + 1

         end

     if @count < @n set @index = 0

     return (@index)

 end

 go

 declare @str varchar(100)

 set @str='A,B,C,D,A,B,C,D,C,D,B,A,C,E'

 select dbo.fn_find('A',@str,1) as one, dbo.fn_find('A',@str,2) as two, dbo.fn_find('A',@str,3) as three, dbo.fn_find('A',@str,4) as four