Re: Possible bridges between OO programming proponents and relational model

From: Marshall <marshall.spight_at_gmail.com>
Date: 3 Jun 2006 08:49:47 -0700
Message-ID: <1149349787.271365.166470_at_j55g2000cwa.googlegroups.com>


Cimode wrote:
> <<Okay; you're discussing the physical layer here. (Although your
> parenthetical remark is incorrect; the choice of a particular
> implementation strategy isn't what determines whether
> you have independence or not.)>>
>
> You consider relvar and R-Table physical layer? Can't agree with that
> (must have missed something).

When you snip as much as you do, it is harder for me to have a dialog. You talked about physical concerns, which I pointed out, and now you say you weren't discussing physical concerns, but you've snipped the paragraph I was responding to, which discussed implementation and physical concerns.

I'll try to be very clear:

In the RM, and in SQL, the logical model is what it is: multidimensional. This is true regardless of the physical implementation.

It might be easier if you picked one level, physical or logical, and stuck to discussing that. When you switch back and forth so quickly, our communication seems to break down.

> << No, I don't think that's correct at all. Physical memory is
> unidimensional;>>
> Please explain your point.

You keep saying that physical representation is two dimensional. But that's not correct. Physical memory is one dimensional; it is a single line of memory from address 0 to address n.

If by "bidimensional" you mean that SQL is always implemented as a simple row store, this is not correct. There are products that are column stores. There are other hybrid approaches. It is not so simple.

> << Well, I wouldn't do that if I were you. I think your best bet is to
> study the existing literature on relational implementation.
> Read ten papers and see if you think OO has something
> useful to say.>> Thanks for the word of caution.(I appreciate) but I
> already started doing that. Diversifying sources helps too. ;)

Marshall Received on Sat Jun 03 2006 - 17:49:47 CEST

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