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Re: Why SHA are 40 bytes? (aka looking for flames)

From
APAndy Parkins <andyparkins@gmail.com>
Date
Apr 21, 2007, 15:08 UTC
Message-ID
<200704211608.06171.andyparkins@gmail.com>
In-Reply-To
<e5bfff550704210635r4008c3c6tf5f55f970bf85e44@mail.gmail.com>
On Saturday 2007, April 21, Marco Costalba wrote:
> Well, why to store always the full length SHA?

Well apart from being easier than working out the optimum size for every single object write, one really good reason would be that there is no way to predict that an object in the future won't have a conflicting SHA - every object /has/ to be stored with its full hash, because you are preventing conflicts with everything object now, in the past and all possible futures.

Wow - git is like a time machine.
Andy
-- 
Dr Andy Parkins, M Eng (hons), MIET
andyparkins@gmail.com
Previous: Marco CostalbaNext: Karl Hasselström
Message 2 of 18 in “Why SHA are 40 bytes? (aka looking for flames)”
  1. Marco CostalbaApr 21, 2007
  2. Andy ParkinsApr 21, 2007
  3. Karl HasselströmApr 21, 2007
  4. Marco CostalbaApr 21, 2007
  5. Marco CostalbaApr 21, 2007
  6. Jon SmirlApr 21, 2007
  7. Marco CostalbaApr 21, 2007
  8. Jon SmirlApr 21, 2007
  9. Marco CostalbaApr 21, 2007
  10. Jon SmirlApr 21, 2007
  11. Andreas EricssonApr 24, 2007
  12. Nicolas PitreApr 24, 2007
  13. Andreas EricssonApr 24, 2007
  14. Nicolas PitreApr 24, 2007
  15. Nicolas PitreApr 22, 2007
  16. H. Peter AnvinApr 24, 2007
  17. Shawn O. PearceApr 24, 2007
  18. Nicolas PitreApr 24, 2007

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