Hi Andréas,
Yes, by globally unique I mean a unique 10-digit ID is assigned to every
model instance of 'Dogs' within my application. This ID will be shown
publicly on the website to allow easy search access to a specific model
instance.
I think you are right about creating a new field to hold the unique ID,
instead of using the primary key. Generating the ID is not too difficult,
but how can I ensure that I won't generate a duplicate ID? From briefly
thinking about it, this is what I got...
When a new instance is created, generate *new ID*
For every *existing ID* in the database:
If *new ID* == *existing ID* in the database:
Generate *new ID* and re-run the for loop
If *new ID* does not match any *existing ID * in the database, proceed with
continuing the model instance.
Also I read up on Signals, but is it necessary?
On Sunday, October 22, 2017 at 12:30:02 PM UTC-4, Andréas Kühne wrote:
>
> Hi,
>
> When you say "globally unique" - I am supposing you mean within your
> application?
>
> What you need to do is set a field to be the primary key, see :
> https://docs.djangoproject.com/en/1.11/topics/db/models/#automatic-primary-key-fields
>
> However - it would be simpler to use the standard primary key auto id
> field, and then add another field to hold your unique ID in it. This could
> then be created on the pre_save signal and you could write something that
> randomly generates the unique ID field. See
> https://docs.djangoproject.com/en/1.11/topics/signals/
>
> Best regards,
>
> Andréas
>
> 2017-10-22 17:52 GMT+02:00 Jack Zhang <[email protected] <javascript:>>:
>
>> Let's say I have a model called 'Dogs'. Users can create instances of
>> Dogs. For every Dogs instance that is created, I want to assign a globally
>> unique ID to it. The ID will be 3 capitalized letters followed by 7
>> numbers. E.g. ABC1234567, POZ2930193
>>
>> What is the easiest way to go about doing this? I looked into UUID but
>> it generates a longer string. Keep in mind that the ID must be globally
>> unique - so after one has been created, it should not be created again.
>>
>> Thanks.
>>
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