is this true ?  I have never experienced the slowdown of the initial 
"traversal" and can't see the need for it - this statement just uses a 
different select list other than zero.  now if the question had been regarding 
SELECTV rather than SELECT, then I would agree.

Gerry



-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] Behalf Of Mats Carlid
Sent: Thursday, July 14, 2005 06:22 AM
To: [email protected]
Subject: Re: [U2] [UV] Select Question


I'm aware of two differences that may be of importance

- if we're speaking uv -

The LIST alternative is immune to a secondary select
inside the loop  -  possibly well hidden in an itype in
a subroutine of an subr....


The bare select lets the readnext loop start emediately
and saves (probably) one traversal of the file.


So yes You'd save overhead - lot's of wall clock time
and io but probably not that much cpu.

hth
-- mats


[EMAIL PROTECTED] wrote:

>Hi all,
>
>Can someone tell me the diference between the following two examples of 
>executing an external select?
>
>SELECT FILE TO LIST
>LOOP
>    READNEXT ID FROM LIST ELSE ID = @AM
>UNTIL ID = @AM DO
>REPEAT
>
>SELECT FILE
>LOOP
>    READNEXT ID ELSE ID = @AM
>UNTIL ID = @AM DO
>REPEAT
>
>Someone pointed out to me that there is overhead in selecting to a list that I 
>need not be exposing myself to.  Aren't they both kind of reading from a list 
>somewhere anyways?
>
>Thanks
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