Re: Object-relational impedence
Date: Wed, 5 Mar 2008 07:58:43 -0800 (PST)
Message-ID: <c9c35623-0dbb-4e9d-b22a-b4451fe0201a_at_s8g2000prg.googlegroups.com>
On Mar 4, 11:10 pm, Robert Martin <uncle..._at_objectmentor.com> wrote:
> On 2008-03-03 18:34:39 -0600, Marshall <marshall.spi..._at_gmail.com> said:
>
> > In SQL, if I have two relations with x and y int columns, I can
> > union them, or join on them, or whatever. There is no way,
> > in fact, to forbid such a thing, just like in Java there is no way
> > to allow such a thing.
>
> You are confusing OO with static typing.
At least you didn't say "duck typing."
> In OO languages like Ruby,
> Python, or Smalltalk you can pass any object to any function
> irrespective of type.
Actually, the dimension I was referring to is "nominal" vs. "structural" typing. This axis is independent of static vs. "dynamic" typing. Ruby, Python and Smalltalk all use structural, dynamic (aka runtime) typing. C++ uses static, nominal typing. Java uses a static, nominal type system with the addition of runtime types; SQL uses static, structural typing.
I was speaking of nominal vs. structural.
Marshall Received on Wed Mar 05 2008 - 16:58:43 CET