Re: Bob's 'Self-aggrandizing ignorant' Count: Was: What databases have taught me

From: Robert Martin <unclebob_at_objectmentor.com>
Date: Sat, 1 Jul 2006 00:45:26 -0500
Message-ID: <2006070100452631729-unclebob_at_objectmentorcom>

On 2006-06-30 01:57:41 -0500, "Marshall" <marshall.spight_at_gmail.com> said:

> George wrote:

>> 
>> Marshall,
>> 
>> Try my description:
>> "The relational model comprises a collection of features useful for
>> constructing large unpredictable state machines from small predictable
>> state machines"
>> 
>> 1. Is that statement true of false?

>
> I suppose the current value of the database could be considered the
> current state, and the empty database the initial state. But there
> are no facilities for specifying messages. There is only insert and
> delete, which map to assignment. There is nothing corresponding
> to an output. So I don't see any way to make it fit the definition.
> My answer is "false."

So then you agree that business rules don't belong in the database. Business rules are, after all, often respresented by the interconnection of many small state machines.

Or are most database engines "turing complete". If they are, then you can of course create interconnected state machines from them.

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Received on Sat Jul 01 2006 - 07:45:26 CEST