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A comment on The One Billion Row Challenge. Parent comment

Re:The One Billion Row Challenge by posix86 on Thursday January 04, 2024 @07:01AM (#38865952)
But how would you detect that a station name is colliding or not colliding? With a hash set?
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Re:The One Billion Row Challenge by viraptor on Thursday January 04, 2024 @07:20AM (#38866082)
Search for cuckoo hashing. It's a whole thing for data structures.
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Re:The One Billion Row Challenge by posix86 on Thursday January 11, 2024 @05:12PM (#38960073)
Cuckoo doesn't aid in detecting collisions, the algorithm is about what happens IF a collision is found. The whole reason we're hashing in the first place is to not have to linearly compare station names when indexing.

In other words: Cuckoo is a strategy to react to the case if two values map to the same hash. But how to know weather you have two different values, or two of the same, if they have an identical hash?

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