this post was submitted on 30 Jun 2024
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Guess the intent (aussie.zone)
submitted 4 months ago* (last edited 4 months ago) by Threen@aussie.zone to c/sql@programming.dev
 

I am one of the developers on a very small team and have just found the following query

I would love to hear your ideas for what you think was being attempted here!

SELECT ... FROM client WHERE CAST(ABS(SIN(clientId)) AS BIT) = 0

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[–] salvaria@lemmy.blahaj.zone 5 points 4 months ago (1 children)

You're right in that any non-zero value casted to bit becomes 1, but that includes negative values, so I'm even more confused why you'd need ABS there...

[–] Jimbabwe@lemmy.world 2 points 4 months ago

Well then, to answer OP’s question about intent, I don’t have much of a clue, but here’s some Idea Ore that maybe someone can refine into a plausible explanation:

  • clientId basically has to be sequential or none of this makes sense
  • conceptually, I believe this statement is equivalent to clientId%180 == 0
  • i can’t fathom CAST(ABS(SIN())) being more efficient than modular division, so maybe the dev was trying to be clever, hated the hardcoded 180, or some other unknown going on
  • a sine wave goes -∿- so this is where it hits the x-axis
  • given that, there has to be some periodic or cyclical purpose, relating to the why/how of the clientId creation. For example, when the results of this are graphed with a created_at timestamp, it might give useful insights to growth (or something)