Hey Eddie!

I like this conversation very much!

Try this with only 100.000 recs!

if object_id ('tempdb.dbo.#TimeTrial') is not null drop table #TimeTrial

create table #TimeTrial (id integer identity(1,1), Event varchar (20), datestart datetime default getdate (), dateend datetime null)

declare @counter integer

set @counter=1

while @counter<13

 begin

  insert #TimeTrial (Event) values ('Richard')

  update HexTest set ASCIIValue = dbo.f_hextostr (HexValue)

  update #TimeTrial set dateend=getdate() where id=@counter

  set @counter=@counter+1

  insert #TimeTrial (Event) values ('Eddie')

  update HexTest set ASCIIValue = dbo.fn_HexToAlpha (HexValue)

  update #TimeTrial set dateend=getdate() where id=@counter

  set @counter=@counter+1

 end

select *, dateend-datestart as diff from #TimeTrial order by id

The result:

1 Richard 00:00:17.333

2 Eddie 00:00:08.283

3 Richard 00:00:06.610

4 Eddie 00:00:08.010

5 Richard 00:00:06.420

6 Eddie 00:00:08.000

7 Richard 00:00:06.520

8 Eddie 00:01:02.360

9 Richard 00:00:06.460

10 Eddie 00:00:07.780

11 Richard 00:00:06.510

12 Eddie 00:00:07.803

Conclusions: The first runs (1-2) must be eliminated, our data not in cash yet. The runs 7-8 must be eliminated, Your result totally differs from others ( really sometimes I don't know, what the hell is running on background), the rest results are comparable.

By the way: our functions are able to run faster, if:

You eliminate the UPPER function (suppose the HEX string is correct);

I eliminate the IF part (suppose the HEX string is correct)

Best regards: Richard