Re: DEFERRABLE NOT NULL constraint

[Andreas Joseph Krogh <andreak@xxxxxxxxxxxx>]

På tirsdag 05. februar 2013 kl. 14:13:20, skrev Chris Angelico <rosuav@xxxxxxxxx>:

On Tue, Feb 5, 2013 at 11:32 PM, Alban Hertroys <haramrae@xxxxxxxxx> wrote:
> On 5 February 2013 12:41, Andreas Joseph Krogh <andreak@xxxxxxxxxxxx> wrote:
>>
>> There are lots of things you can do, but when it's the ORM which does it
>> you have limited control, and that's the way it should to be (me as
>> application-developer having to worry less about such details).
>
> In that case it's your ORM that needs fixing, not the database.

Agreed. One of the differences between MySQL and PostgreSQL is that
the latter gives you a database with rules, while the former is a
place for an application to store data. This last couple of weeks I've
been working with a really sloppily-built application (and a very
popular one too, so I won't name names), and it fits MySQL
perfectly... What I'd much rather do is build real rules that may not
EVER be violated. While I can see the value in deferring foreign key
constraints (circular references - never used 'em though), I don't see
any reason to create a record with a NULL and then replace that NULL
before committing. Sort out program logic first; then look to the
database.

Making people's lives easier in the short term is NOT the greatest
goal of a database. Consistent data will make the admins' lives far
easier in the long term. I do not ever want to have to deal with
BTrieve file corruption in my life.

 

I've been using PG since v-6.5 and I'm very aware of its strengths, and also its weaknesses. There really isn't an argument for not having NOT NULL deferrable constraints, other than -hackers not prioritizing it, which I understand perfectly well as they have lots of other interesting stuff on their plate.

 

--
Andreas Joseph Krogh <andreak@xxxxxxxxxxxx>      mob: +47 909 56 963
Senior Software Developer / CTO - OfficeNet AS - http://www.officenet.no
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