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Guess the intent (aussie.zone)

submitted 7 months ago* (last edited 7 months ago) by [email protected] to c/[email protected]

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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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[–] [email protected] 6 points 7 months ago (3 children)

Well abs(sin(x)) is always going to return a value between 0 and 1, and I dunno how casting to bit works.. if it rounds this might be used to consistently grab half the users. If CAST(anything except 0) as BIT —> 1, then this could be used to grab a very small subset of users? If their clientIds happen to be clientId%180 == 0

[–] [email protected] 3 points 7 months ago

I forgot to mention this is in SQL Server, so SIN operates on radians. So I THINK this can only ever cast to a 0 when clientId is also 0

It certainly doesn't for any of the 100,000 existing rows

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