[EMAIL PROTECTED] wrote on 07/22/2005 10:08:02 PM:

> > >>     READNEXT ID FROM LIST ELSE ID = @AM 
> > >But why do you use an odd convention like ID = @AM ?
> 
> because it would be impossible for ID to be an attribute mark via
> readnext.
> If you later test for ([EMAIL PROTECTED]) there's only one way that could have
> happened.
> 

I started to use this syntax (ELSE ID = @AM) several years ago.  It 
originated, I think, from the "Advanced Pick Programming" book, circa 
1990.  The theory went that if you used a separate variable, usually EOF, 
in the ELSE clause, the variable would get forced out of memory and would 
have to be read back in from disk for each subsequent READNEXT.  The 
attribute mark, on the other hand, was usually equated.  On the systems of 
that time, this resulted in a fairly big improvement in larger programs. 
In small programs, where everything fit into memory, this would not 
provide any benefit.

These days, I still use the syntax because I my fingers can type it from 
memory, without my brain actually working.

Charlie Rubeor
Unix/Database Admin
The Wiremold Company
800.338.1315 x3498
860.523.3690 fax
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