I recently viewed a post that said "autonumber is fine as long as you dont 
display it to the user..."   Everything in my database references 
autonumbers!!  did i make a big mistake somewhere??  i am even marking parts 
with ID numbers that are generated by the autonumber field on a few of my 
tables...

Should i be worried??

Do i need to seriously look into a new approach??

any comments are greatly appreciated..

Barry

There is nothing wrong with autonumbers, even in more advanced dbs dbas 
create a form of autonumber (they call it differently but it serves the same 
purpose).

The problem is that many people mistakenly try to rely on autonumbers as, 
for instance, a document number.  It is merely a unique id associated to a 
record.  In reality it should serve no other purpose.  The end user should 
even be aware of autonumber.  If you need to number your records and display 
it to the user, ie a sequential number associated to a document, then create 
a custom field in your table for this distinct purpose.

Short answer, there is nothing wrong with autonumber, but rather the way 
some people mistakenly try an use them.

Don't worry!
-- 
Hope this helps,

Daniel Pineault
http://www.cardaconsultants.com/
For Access Tips and Examples: http://www.devhut.net
Please rate this post using the vote buttons if it was helpful.



"Barry A&P" wrote:

> I recently viewed a post that said "autonumber is fine as long as you dont 
> display it to the user..."   Everything in my database references 
> autonumbers!!  did i make a big mistake somewhere??  i am even marking parts 
> with ID numbers that are generated by the autonumber field on a few of my 
> tables...
> 
> Should i be worried??
> 
> Do i need to seriously look into a new approach??
> 
> any comments are greatly appreciated..
> 
> Barry

Same as what Daniel said...couple more notes. 

When it's said to never show it to the outside world,  that's to guard 
against anybody ever trying to change one.    The minute you try to use them 
for a real world use, you run the risk of somebody with more authority than 
brains or listening skills dictating a change or reassignment of a number 
which violates an important and essential database principle.      

Barry A&P wrote:

> I recently viewed a post that said "autonumber is fine as long as you dont
> display it to the user..."   Everything in my database references
> autonumbers!!  did i make a big mistake somewhere??  i am even marking
> parts with ID numbers that are generated by the autonumber field on a few
> of my tables...
> 
> Should i be worried??
> 
> Do i need to seriously look into a new approach??
> 
> any comments are greatly appreciated..

In my opinion "never expose AutoNumbers to users" is vastly overstated.  It 
is based on an assumption that users will make assumptions that might 
confuse them (like the values should not have gaps).

Well, amongst users the stupid ones will make assumptions that confuse them 
about LOTS of things.  The smart ones not so much.  Many situations will 
never expose a long continuous block of records to a user at one time where 
an assumption about gaps comes into play anyway.

There are cases where the "business rules" dictate no gaps.  In those cases 
avoid AutoNumbers.  There is little reason to avoid them (and show them to 
users) when business rules don't care.

Barry

What Daniel and Fred said ...

Access Autonumbers are designed to serve as unique row identifiers, nothing 
else.  As such, they are rarely suitable for human consumption.

Keep using them as unique row identifiers, but don't expect your users to 
understand ... OR CARE!

If you want your users to care about some number, use Daniel's approach and 
create a new field, in addition to your autonumber field.  Use that new 
field to hold a "sequence number".  That one's OK to show the users...

(and all things in moderation... a fellow whose experience I greatly respect 
quite often displays autonumbers to his user ... but he has a very high 
class of users ...<g>)

Regards

Jeff Boyce
Microsoft Access MVP

-- 
Disclaimer: This author may have received products and services mentioned
in this post. Mention and/or description of a product or service herein
does not constitute endorsement thereof.

Any code or pseudocode included in this post is offered "as is", with no
guarantee as to suitability.

You can thank the FTC of the USA for making this disclaimer
possible/necessary.

"Barry A&P" <BarryAP@discussions.microsoft.com> wrote in message 
news:30984979-018A-4DB1-AE3F-9BEDADF0833A@microsoft.com...
>I recently viewed a post that said "autonumber is fine as long as you dont
> display it to the user..."   Everything in my database references
> autonumbers!!  did i make a big mistake somewhere??  i am even marking 
> parts
> with ID numbers that are generated by the autonumber field on a few of my
> tables...
>
> Should i be worried??
>
> Do i need to seriously look into a new approach??
>
> any comments are greatly appreciated..
>
> Barry 

On Wed, 28 Apr 2010 14:59:31 -0700, "Jeff Boyce"
<nonsense@nonsense.com> wrote:

>What Daniel and Fred said ...

Me too!

>Access Autonumbers are designed to serve as unique row identifiers, nothing 
>else.  As such, they are rarely suitable for human consumption.

Rarely, but not never.

>If you want your users to care about some number, use Daniel's approach and 
>create a new field, in addition to your autonumber field.  Use that new 
>field to hold a "sequence number".  That one's OK to show the users...
>
>(and all things in moderation... a fellow whose experience I greatly respect 
>quite often displays autonumbers to his user ... but he has a very high 
>class of users ...<g>)

We sometimes let the users see an Autonumber, when they need to
correctly identify one record among many similar records -
transactions for example.  Of course they can't change it, and we tell
them not to worry about gaps in the sequence.  Once we explain that
it's just a unique "Reference Number" (we actually sometimes call it
that in the UI), they seem to do just fine with it.  It's easier than
building our own sequence number.

Armen Stein
Microsoft Access MVP
www.JStreetTech.com
 

=?Utf-8?B?RnJlZA==?= <Fred@discussions.microsoft.com> wrote in
news:38736AAF-BC0B-4D48-92E9-0B719B0FDCFC@microsoft.com: 

> When it's said to never show it to the outside world,  that's to
> guard against anybody ever trying to change one. 

Er, what? Autonumbers aren't editable, so there's no danger even
*if* somebody is tempted to change one. 

The problem is that people invest MEANING in Autonumber values and
assume they are sequential and have no gaps. An Autonumber is really
just a special type of default value for a Long Integer field (you
can append any value to it you like that doesn't violate an existing
index). It can, in fact, be random (and *is* random in a replicated
Jet database). 

The values of an Autonumber field have no meaning. Exposing them to
the user tempts them to invest the values with meaning, and that's
the flaw. 

-- 
David W. Fenton                  http://www.dfenton.com/ 
usenet at dfenton dot com    http://www.dfenton.com/DFA/

On Wed, 28 Apr 2010 13:11:01 -0700, Barry A&P
<BarryAP@discussions.microsoft.com> wrote:

>I recently viewed a post that said "autonumber is fine as long as you dont 
>display it to the user..."   Everything in my database references 
>autonumbers!!  did i make a big mistake somewhere??  i am even marking parts 
>with ID numbers that are generated by the autonumber field on a few of my 
>tables...
>
>Should i be worried??
>
>Do i need to seriously look into a new approach??
>
>any comments are greatly appreciated..
>
>Barry

Just one other caveat in addition to the good points made by the other
responders: if you ever Replicate your database (which you won't if it's in
2007 or 2010, that feature has been removed), all your autonumbers will become
random. The next three records might have autonumber values of -228412113,
1924443671 and -889225013. If that won't freak out your users nothing will!
-- 

             John W. Vinson [MVP]

I am in fact using the autonumber field because i Need a Unique Identifier 
for each item.  I tried the Consecutive number approach but had many cases 
where using DMax+1  then the last record was deleted and the number was 
re-created--  I am in Access 2007 and dont know if i will ever need to 
replicate (whatever that does) so for now i will cross my fingers and hope i 
dont ever see -32481927 as a Unique Identifier for one of my parts..  Cross 
that bridge when i get there i guess...

Thank you everybody for your input..

Barry

"Armen Stein" wrote:

> On Wed, 28 Apr 2010 14:59:31 -0700, "Jeff Boyce"
> <nonsense@nonsense.com> wrote:
> 
> >What Daniel and Fred said ...
> 
> Me too!
> 
> >Access Autonumbers are designed to serve as unique row identifiers, nothing 
> >else.  As such, they are rarely suitable for human consumption.
> 
> Rarely, but not never.
> 
> >If you want your users to care about some number, use Daniel's approach and 
> >create a new field, in addition to your autonumber field.  Use that new 
> >field to hold a "sequence number".  That one's OK to show the users...
> >
> >(and all things in moderation... a fellow whose experience I greatly respect 
> >quite often displays autonumbers to his user ... but he has a very high 
> >class of users ...<g>)
> 
> We sometimes let the users see an Autonumber, when they need to
> correctly identify one record among many similar records -
> transactions for example.  Of course they can't change it, and we tell
> them not to worry about gaps in the sequence.  Once we explain that
> it's just a unique "Reference Number" (we actually sometimes call it
> that in the UI), they seem to do just fine with it.  It's easier than
> building our own sequence number.
> 
> Armen Stein
> Microsoft Access MVP
> www.JStreetTech.com
>  
> .
> 

Thanks Jeff

I needed to see this line

"(and all things in moderation... a fellow whose experience I greatly respect 
quite often displays autonumbers to his user ... but he has a very high 
class of users ...<g>)
"

Barry

"Jeff Boyce" wrote:

> Barry
> 
> What Daniel and Fred said ...
> 
> Access Autonumbers are designed to serve as unique row identifiers, nothing 
> else.  As such, they are rarely suitable for human consumption.
> 
> Keep using them as unique row identifiers, but don't expect your users to 
> understand ... OR CARE!
> 
> If you want your users to care about some number, use Daniel's approach and 
> create a new field, in addition to your autonumber field.  Use that new 
> field to hold a "sequence number".  That one's OK to show the users...
> 
> (and all things in moderation... a fellow whose experience I greatly respect 
> quite often displays autonumbers to his user ... but he has a very high 
> class of users ...<g>)
> 
> Regards
> 
> Jeff Boyce
> Microsoft Access MVP
> 
> -- 
> Disclaimer: This author may have received products and services mentioned
> in this post. Mention and/or description of a product or service herein
> does not constitute endorsement thereof.
> 
> Any code or pseudocode included in this post is offered "as is", with no
> guarantee as to suitability.
> 
> You can thank the FTC of the USA for making this disclaimer
> possible/necessary.
> 
> "Barry A&P" <BarryAP@discussions.microsoft.com> wrote in message 
> news:30984979-018A-4DB1-AE3F-9BEDADF0833A@microsoft.com...
> >I recently viewed a post that said "autonumber is fine as long as you dont
> > display it to the user..."   Everything in my database references
> > autonumbers!!  did i make a big mistake somewhere??  i am even marking 
> > parts
> > with ID numbers that are generated by the autonumber field on a few of my
> > tables...
> >
> > Should i be worried??
> >
> > Do i need to seriously look into a new approach??
> >
> > any comments are greatly appreciated..
> >
> > Barry 
> 
> 
> .
> 

John W. Vinson <jvinson@STOP_SPAM.WysardOfInfo.com> wrote in
news:v8mht51jnderu7kki97gvupjte9k21lt4q@4ax.com: 

> if you ever Replicate your database (which you won't if it's in
> 2007 or 2010, that feature has been removed),

No, that has *not* been removed. A2007 and A2010 and the ACE all
still support Jet replication, just not in ACCDB format, but only in
MDB format. 

The lack of replication (and ULS) is a FILE FORMAT issue, not an
application or database engine issue. 

-- 
David W. Fenton                  http://www.dfenton.com/ 
usenet at dfenton dot com    http://www.dfenton.com/DFA/

Of course you are right.  I was mixing two topics together there (came from 
assuming that the autonumber is also the PK) but I think that my statement 
about the potential issue still is useful.