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A comment on Two Bits Are Better Than One: making bloom filters 2x more accurate.

Re:Two Bits Are Better Than One: making bloom filters 2x mor... by h33t-l4x0r on Sunday February 22, 2026 @12:16AM (#47108425)
Hmm, Bloom filters seem important. I'm wondering why my CS education never even touched on them and it's tbh triggering my imposter syndrome.
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Re:Two Bits Are Better Than One: making bloom filters 2x mor... by benmanns on Sunday February 22, 2026 @12:51AM (#47108595)
They were only touched on (and just barely) in my CS education, so don’t feel too left out. Spend an evening or two on the Wiki for Probabilistic data structures[0]. With a CS education you should have the baseline knowledge to find them really fascinating. Enjoy!

Oh, and I don’t find myself actually implementing any of these very often or knowing that they are in use. I occasionally use things like APPROX_COUNT_DISTINCT in Snowflake[1], which is a HyperLogLog (linked in the Wiki).

[0]: https://en.wikipedia.org/wiki/Category:Probabilistic_data_st...

[1]: https://docs.snowflake.com/en/sql-reference/functions/approx...

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Re:Two Bits Are Better Than One: making bloom filters 2x mor... by dheera on Sunday February 22, 2026 @02:03AM (#47108916)
My education didn't touch upon it but I've been grilled on it multiple times in interviews.

I learned about them after the first time I got grilled and rejected. Sucks to be the first company that grilled me about it, thanks for the tip though, you just didn't stick around long enough to see how fast I learn

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Re:Two Bits Are Better Than One: making bloom filters 2x mor... by vyr on Sunday February 22, 2026 @02:26AM (#47109040)
they're common in databases and performance instrumentation of various kinds (as are other forms of data structure "sketch" like count sketches) but not as common outside those realms.

i've gotten interview questions best solved with them a few times; a Microsoft version involved spell-checking in extremely limited memory, and the interviewer told me that they'd actually been used for that back in the PDP era.

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Re:Two Bits Are Better Than One: making bloom filters 2x mor... by on_the_train on Sunday February 22, 2026 @05:14AM (#47109839)
Unpopular opinion: They're one of these things that are popular because of their cool name. For most purposes, they're not a good fit
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Re:Two Bits Are Better Than One: making bloom filters 2x mor... by jb3689 on Sunday February 22, 2026 @08:42AM (#47110933)
Distributed systems and probabilistic data structures really should be in every undergrad CS curriculum even if just in passing for the second
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Re:Two Bits Are Better Than One: making bloom filters 2x mor... by hinkley on Sunday February 22, 2026 @02:20PM (#47113786)
That curriculums didn’t have distributed computing classes when I was in school (mine did, but few took it) made some sense. That modern coursework omits it is unconscionable.
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Re:Two Bits Are Better Than One: making bloom filters 2x mor... by hinkley on Sunday February 22, 2026 @02:17PM (#47113768)
I made it until Google posted an article about their use of Bloom Filters back around -2000 before I even heard of them, which is at least 25 years after they were invented. Anger was my emotion, not impostor syndrome. I went to a top ten school and none of my profs thought to mention it. Had to learn AVL trees twice though. Which I’ve used fuck-all.
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