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Re: Columnar databases



Kristoffer Sjögren wrote:
My idea is to have one bit index per logical column+value stored in a
value where the key also have some means of partitioning the data,
maybe over time. So high cardinality columns will generate lots of
keys+values.

I was thinking of storing multiple indexes in each key+value, making
values bigger but fewer. Say around a few hundreds kilobytes each.

Are there any trade offs between many smaller key+value vs fewer
larger ones? I'm more concerned about read performance.

There would be a speed advantage to using fewer keys+larger values. Search performance is O(logN) where N is the number of keys...

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