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A comment on Challenges students face when learning to work with relational databases and SQL. Parent comment

Re:Challenges students face when learning to work with relat... by fifilura on Monday August 30, 2021 @02:28AM (#28353239)
1. GP mentioned hairy self joins 2. You replied with an example 3. I pointed out that there are other examples.

That said, I have a feeling your duplicates can be fixed by adding the requirement that c.cid < c2.cid

Not sure a window function would help in this particular situation, but they are there to help in more mundane examples.

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Re:Challenges students face when learning to work with relat... by weaksauce on Monday August 30, 2021 @02:11PM (#28358922)
I see how it can be read that way yeah. they mentioned the study used a self join problem that they couldn't likely figure out so I looked at the paper and quickly did it off the top of my head. the less than predicate does indeed do the trick.
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