Re: Object-relational impedence

From: frebe <>
Date: Thu, 13 Mar 2008 22:17:40 -0700 (PDT)
Message-ID: <>

On 13 Mar, 18:40, Robert Martin <> wrote:
> The real point of that remark was that the user of a tool is at a
> higher level of abstraction than the tool itself.  SQL is a tool.  ORMs
> are tools that use SQL to get their job done, just like compilers use
> assembly to get their job done.  In that sense ORMs live at a higher
> level of abstraction than SQL.

Lets have an example: There are many "compiler" products translating from a high-level language like ADA to a low-level language like C, instead of translating to machine code directly. What if someone wrote a "compiler" translating C source code to ADA source code, would that make C more high level than ADA? Hardly? The existance of a product translating from language A to language B doesn't say anything about the levels of A and B.

> The members of c.d.t. might respond negatively to that idea because
> they see SQL as a better vehicle to do the job that the ORM is trying
> to do. That's fine, but does not change the fact that the ORM is using
> SQL as an implementation language.

If a RDBMS product is implemented using an OOPL, does that make relational algebra more high level than OO?

//frebe Received on Fri Mar 14 2008 - 06:17:40 CET

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