Berkeley CSUA MOTD:Entry 24554
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2025/05/25 [General] UID:1000 Activity:popular
5/25    

2002/4/23-24 [Computer/SW/Database, Computer/Theory] UID:24554 Activity:high
4/34    Most databases use B-tree structure to store the data.  Is there a
        mathematical proof that this is the most efficient way to store
        a dbase?  Best in update times, delete times, record sizes, etc?
        I'm wondering if there are better structures for specific structures.
        Like a database full of numbers is different from a database of
        words.  thanks.
        \_ Proving lower bounds on storage space of an arbitrary object is
           undecidable (it reduces to finding the Kolmogorov complexity of
           the said object). -- ilyas
           \_ You meant "reduces from," of course... (the other direction does
              not imply uncomputability; and there are other issues with
              storage of arbitary data structures [e.g. efficiency of
              later access]). -alexf
              \_ Sorry, I wasn't using 'reduces' in the technical sense, I just
                 meant the two problems are equivalent, but yes.  If I had a
                 terminating algorithm for proving lower bounds on storage
                 space I could use that algorithm to find the Kolmogorov
                 complexity of an object, which isn't possible.  Interestingly
                 enough, some lower bounds on running time of data access exist
                 (O(log n)). -- ilyas
        \_ Uh, the insert/delete/search bounds are well known and well
           understood.  STFW or read a databases book to find out and draw
           your own conclusions.  They are not by any means the best, but,
           they are good for many of the more common operations that are done
           on a database, and not too bad (TM) on the less common operations.
           And the fact that you ask if the performance would be different for
           a database of numbers vs. words shows a gross misunderstanding of
           what the hell a database is.
2025/05/25 [General] UID:1000 Activity:popular
5/25    

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