Re: Unique and null

Many thanks

Mike

--

(Unsigned mail from my phone)

-------- Original message --------

From: "Ing.Daniel Bojorge" <debs.foros@gmail.com>

Date: 8/4/21 08:59 (GMT+10:00)

To: django-users@googlegroups.com

Subject: Re: Unique and null

I suggest that if you set unique, the field must have value, so null=False.

Blank=True es for form and template, to set required.  Null es for database.

Dios L@s Bendiga

Saludos,

daniel.bojorge about.me/daniel.bojorge

Curso Desarrollo Web con Python usando Django 2.2 Para Principiantes con Descuento 95%   

WebService RestFul API con Python usando Django RestFrameWork

Fácil Replicación de Cualquier Base de Datos y/o Sistema Operativo

Programación en Capas (Web y Escritorio)

Mi Blog

Nicaragua

"Si ustedes permanecen unidos a mí, y si permanecen fieles a mis enseñanzas, pidan lo que quieran y se les dará.
(Juan 15:7 DHH)
Bendito el varón que se fía en el SEÑOR, y cuya confianza es el SEÑOR.
(Jeremías 17:7 RV2000)

El mié, 7 abr 2021 a las 16:52, Mike Dewhirst (<miked@dewhirst.com.au>) escribió:

No. PostgreSQL.

I checked that post. And googled the answer. Postgres follows the SQL standard and permits multiple nulls in a unique column.

I should have done that instead of asking. I had first thought of it being a Django thing and couldn't find the answer in the docs.

Thanks for responding.

Cheers

Mike

--

(Unsigned mail from my phone)

-------- Original message --------

From: Derek <gamesbook@gmail.com>

Date: 7/4/21 23:05 (GMT+10:00)

To: Django users <django-users@googlegroups.com>

Subject: Re: Unique and null

Are you using MySQL?

https://stackoverflow.com/questions/3712222/does-mysql-ignore-null-values-on-unique-constraints

On Wednesday, 7 April 2021 at 08:07:35 UTC+2 Mike Dewhirst wrote:

I have just made a CharField unique and Django detects duplicates nicely
but seems to ignore multiple instances where the field value is null.

    arn = models.CharField(
        max_length=MEDIUM,
        unique=True,
        null=True,
        blank=True,
    )

Is this correct behaviour?

Thanks

Mike



--
Signed email is an absolute defence against phishing. This email has
been signed with my private key. If you import my public key you can
automatically decrypt my signature and be sure it came from me. Just
ask and I'll send it to you. Your email software can handle signing.

--
You received this message because you are subscribed to the Google Groups "Django users" group.
To unsubscribe from this group and stop receiving emails from it, send an email to django-users+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/django-users/efd40f22-50d8-4250-9738-95d2152e68ecn%40googlegroups.com.

--
You received this message because you are subscribed to the Google Groups "Django users" group.
To unsubscribe from this group and stop receiving emails from it, send an email to django-users+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/django-users/606e377e.1c69fb81.2c612.06e5SMTPIN_ADDED_MISSING%40gmr-mx.google.com.

--
You received this message because you are subscribed to the Google Groups "Django users" group.
To unsubscribe from this group and stop receiving emails from it, send an email to django-users+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/django-users/CAMQeQjbA%3D6GG--TwG3ja8L%2B-2%2BtRnMfH3_jrPvrZ%2B5tTgPmGYA%40mail.gmail.com.