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From Jean-Daniel Cryans <jdcry...@apache.org>
Subject Re: Hfile - Storefile
Date Wed, 01 Sep 2010 17:18:44 GMT
StoreFile is just a wrapper for HFile to add HBase-sugar on top of it.


On Wed, Sep 1, 2010 at 8:16 AM, Himanshu Vashishtha
<vashishtha.h@gmail.com> wrote:
> It will be great if anyone point out the difference in their functionality.
> What I understand is Storefile is made persistent in fs, compactions
> occurred on these (to me, its an equivalent of SSTable).
> Hfile is derived (evolved) from MapFile, giving access to faster random
> reads (as it uses index to look for a key etc). Is it a handler sort of to
> access the persisted Storefile? By their package structure, i think so
> (Hfile is in io, storefile is in rs).
> Now, the interesting thing is I know I am possibly wrong. As Ryan pointed
> out recently:"Hfiles are write once read many. Once written they cannot be
> modified so there is way to move things around."...
> This is a SSTable property: they are immutable. And they are merged into one
> by compactions (major).
> I will appreciate if you please provide the missing link.
> Thanks,
> ~Himanshu

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