Just to be clear on 2 things

1)
> And thanks to Tim Lucas who recently brought to light the ability to use 
> @@IDENTITY in mySQL v4+.

@@IDENTITY is NOT supported in mySQL.  Tim got mistaken about which DB we were talking 
about. In mySQL you use Last_INSERT_ID().
(Use http://www.mysql.com/search/index.php?q=@@IDENTITY&from=%2Findex.html if you 
doubt me)

2) If you are using a DB with stored procs, it's a minute DB hit to do your insert and 
return the 
ID out of the Database after you have done it.  To do the 2 queries out of ColdFusion 
will, by 
definition, be slowler, as the stored proc is already AT the DB.

On a final note -

If you want to generate your own ID so you 'know what it is' I would suggest still 
sticking to a 
numeric value.  Something you generate with some year-month-day-second-millisecond 
values 
and some random fields.  I used to do this as well, and it was a reliable solution.

However, to hit the DB One more time on an INSERT to get an IDis not worth the overall 
performance degredation that a DB running joins on a UUID is going to cause.

But it's all about trade offs in the long run, maybe it makes more sense in your apps.

It kinda boils down to - how long is a piece of string?

Mark

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Quoting Brett Payne-Rhodes <[EMAIL PROTECTED]>:

> @@IDENTITY may solve the 'lock' issue but it is still another trip to 
> the database to actually retrieve it. Personally I don't have a problem 
> with doing it but let's be clear about what is and is not true.
> 

> 
> Brett
> B)
> 
> Taco Fleur wrote:
> > This article is 5 years old..
> > 
> > "The problem with these is that finding the PK value of a newly inserted
> > record requires another trip to the server and the DB -- and a lock on the
> > database file while the DB determines the last ID inserted."
> > 
> > This is not true for MS SQL, you simple use @@IDENTITY or SCOPE_IDENTITY
> > 
> > 
> > Taco Fleur
> > Blog http://www.tacofleur.com/index/blog/
> > Methodology http://www.tacofleur.com/index/methodology/
> > 
> > Tell me and I will forget
> > Show me and I will remember
> > Teach me and I will learn 
> > 
> > 
> > 
> >>-----Original Message-----
> >>From: [EMAIL PROTECTED] 
> >>[mailto:[EMAIL PROTECTED] On Behalf 
> >>Of Yorke Hinds
> >>Sent: Thursday, 12 February 2004 9:57 AM
> >>To: CFAussie Mailing List
> >>Subject: [cfaussie] Re: Whats your Primary Key?
> >>
> >>
> >>I am using SQL Server.
> >>
> >>In 1999 Hal Helms wrote a brief article on the subject - 
> > 
> > http://www.halhelms.com/index.cfm?fuseaction=newsletters.aug1999
> > 
> > Any comments regaring Hals Article?
> > 
> > 
> > 
> > 
> > 
> > 
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> 
> -- 
> Brett Payne-Rhodes
> Eaglehawk Computing
> t: +61 (0)8 9371-0471
> f: +61 (0)8 9371-0470
> m: +61 (0)414 371 047
> e: [EMAIL PROTECTED]
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