Re: Object-relational impedence

From: Robert Martin <>
Date: Thu, 13 Mar 2008 12:40:22 -0500
Message-ID: <2008031312402277633-unclebob_at_objectmentorcom>

On 2008-03-12 10:11:54 -0500, topmind <> said:

> You "downplay" RDBMS.

Over the years I have learned to do that a lot less. There was a time that I considered DBs to be "a bucket of bits". Thanks, in part, to these crossposted discussions between c.o and c.d.t I have come to have a very different opinion.

> You compared queries to "assembler language" in
> one reply, for example. While not a direct "attack" it is the next
> nearest thing.

I can undertand why someone might take offense at that, if one thought that there was something awful about assembly language.

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.

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.

Robert C. Martin (Uncle Bob)  | email:
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Received on Thu Mar 13 2008 - 18:40:22 CET

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