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Is the relative clause a defining relative clause or non-defining?

So the isolation property too is really more of a desideratum than an ironclad guarantee: What is more, real-world systems typically provide explicit mechanisms namely, isolation levels lower than the maximum--whose effect is precisely to undermine isolation.

Introduction to Database Systems, J. Date

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First, please tell us which word you see this clause as relative to.

Clive

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I agree.

Now if we say "What is more, real-world systems typically provide explicit mechanisms whose effect is precisely to undermine isolation", are there other explicit mechanisms that have other effects?

Clive

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I really don't know whether or not there are other explicit mechanisms that have other effects.

no other explicit mechanisms Then it is not a defining clause.

other explicit mechanisms Then it is a defining clause


In my opinion, it's a poorly written sentence because the dash just tacks on what follows as an after-thought and leaves the reader trying to figure out what the writer meant. A comma instead of a dash is a lot easier to interpret.

What is more, real-world systems typically provide explicit mechanisms comma namely isolation levels lower than the maximum, whose effect is precisely to undermine isolation.

Clive

Comments  

Explicit mechanisms

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 Clive's reply was promoted to an answer.

Many thanks, Clive!

I really don't know there are other explicit mechanisms that have other effects or not Emotion: sad

From the sentence isn't this clear, please?

 Clive's reply was promoted to an answer.
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Many thanks Clive for the excellent explanation!!!