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Comment by drw85 | Hacker News Reader

I don't really understand the need for developers to find some real world scenario or situation that they can use as analogy.

Impedance mismatch is a physical thing, it creates physical problems that are based on laws in nature. Having to map your database entities to a model that is different has nothing to do with any physical things, it's a mental construct.

If you have a mismatch of impedance, what do you do? You insert something between the two mismatched devices to match the impedance. Isn't that what all software does already anyways? Insert some mapping, converting, transforming layer between the two pieces?

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Yeah, I agree - I'm really anti the over-use (and there is a lot of that) of bad analogies in the software development community - I've never seen the attraction myself. And I'm speaking as someone that has done a lot of teaching in this area.

But at least this one is not particularly harmful or obfuscatory - you have A and B and you need to frig things so they can talk to each other.

It kind of is?

When I have conversations about this, I encounter the term "object/relational impedance mismatch" a lot more often than I encounter people who really have a thorough understanding of what the term describes and why it exists.

It often seems to me like the way it functions in our profession is a lot like the way the word "quantum" functions in Deepak Chopra's vocabulary. It's not really a specific, definable thing, so much as an amorphous, esoteric cosmic principle that can be used as a universal logical connector for stitching together any arbitrary chain of reasoning.

Which is too bad. I don't think it's actually a particularly difficult concept, when you get down to it. But I do think that the fancy-sounding technical name for the concept tends to obfuscate its meaning by making it sound like a much bigger deal than it actually is.

Completely agree about the Object-relational mismatch. The general term "Impedance Mismatch" is used in several industries to mean the loss in efficiency due to increase in complexity.

"Object-Relational Impedance Mismatch"[1] is been around for decades. Martin Fowler[2] and others who are deeply technical (think Sr. architects, CTOs) use this all the time.

[1] https://en.wikipedia.org/wiki/Object%E2%80%93relational_impe... [2] https://youtu.be/qI_g07C_Q5I?t=98

Sometimes novel analogies lead to novel solutions.

Can you specify a single instance of this?

GUI as a desktop.

Well, I think that has been somewhat over-rated. Looking at my physical desktop now, I don't see any little "X" icons on the beer bottles littering it, or anything analogous (wish there was). And I hardly ever use the Windows desktop, and haven't for many years, even though I use Windows almost all the time.

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