create function fn_findstr(@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