Is it completly random or the next in a sequence? (i.e. aa0000, aa0001, etc.) Either way, I suspect you'd need to generate an ID and then query the database to make sure it's not in use. It's possible to do this in a stored procedure if you're using MS SQL.

 

It is for use in WWF or a different application?

 

Jono

 

You may also want to look at SQL Express - it's free and ideal for a development environment and without the need to modify code from Access to SQL Server.

 

I appreciate what you're saying about guessing ID's in a sequence, but it's bad to have "security by obsecurity" - if someone, for example, want's to view an invoice, it should either be their invoice or they should be a sys admin, otherwise they should be directed to another page.

 

GUID's are special type of ID's and, as you've guessed, not exactly what you're after.

 

I hope the above helps, but let me know if i can clarify anything for you.

 

i see what you want regarding security , you can use prefixes and hex values and timers

 

 

INV-AccID-RANDOMNumber(5)

 

and using a MOD 2 = 0 function within the random number function. using your Acc to randoimise the sections being used like SECOND(NOW()), and Value = round(odd/Second)

and depending on that use different MOD 3 = 3 or others to create random

 

and place into a DB

 

just a few ideas , simular with my security measures i use in my Apps (require to be secure)

 

 

thinking on making it unique , most ways will require  a DB check, because any check may result in an other record.

 

its making enough veriables time is usually a good start point to make it random.

 

 

 

Hi Stardust,

 

I understand a bit better what you're trying to achieve. So let's make it a bit simpler for ourselves. As DJ's said, you can create your own Unique ID's, but you'll have to check them. Autonumbers are already checked, but they are squential, and not what you're after.

 

So, were back on to GUID's - yes, i know this is where you started, sorry about that.

 

I'm going to assume you're going to use SQL2005 (in one version or another) rather than writing two versions of your code. Here are some links about generating GUIDs:

 

http://www.sqlservercurry.com/2007/12/generate-unique-number-in-sql-server.html - http://www.sqlservercurry.com/2007/12/generate-unique-number-in-sql-server.html

http://www.sqlteam.com/forums/topic.asp?TOPIC_ID=104575 - http://www.sqlteam.com/forums/topic.asp?TOPIC_ID=104575

 

and finally WIKI ('cos it's always correct ): http://en.wikipedia.org/wiki/Globally_Unique_Identifier - http://en.wikipedia.org/wiki/Globally_Unique_Identifier

 

The first link also shows some conversion options. Because the number is autogenerated, it's a 32 byte number and (i believe) the length cannot be changed. If you do want to represent it in a shorter fashion, you could try writing a routing to change the base.

 

For example hex is base 16 (0-9,A-F), but you could use base 36(0-9,A-Z) or some other base [base62 - 0-9,A-Z,a-z - this get more complicated!]. I did write a converter in Pascal as a college project, but that was ages ago!

 

I think the NEWID() function is the way forward for you, but let us know what you think.

 

Jono