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HBase >> mail # dev >> KeyValueScanner

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Re: KeyValueScanner
Thanks Lars - i guess i had it backwards.
On Wed, Sep 12, 2012 at 10:38 PM, lars hofhansl <[EMAIL PROTECTED]> wrote:

> reseek is forward only. So a scanner can potentially make use of that fact.
> A seek can seek to any KV even if that means the scanner is rewound (so to
> speak) to a KV that sorts before the current one.
> For example see the implementations of seek(...) and reseek(...) in
> MemstoreScanner.
> Is that what you were asking?
> -- Lars
> ________________________________
>  From: Matt Corgan <[EMAIL PROTECTED]>
> Sent: Wednesday, September 12, 2012 10:25 PM
> Subject: KeyValueScanner
> Hi guys - I'm working on an interface for KeyValue and also trying to
> figure out what changes we need to make to KeyValueScanner for prefix
> compression.  One thing that's confusing me is the difference between the
> seek() and reseek() methods.  Could someone take a stab at explaining those
> since the javadoc is not of much help (kinda circular definition)?
> I'd rather not even pollute this email with my best guess, but i think it
> has something to do with reseek being used when you estimate you'll have to
> seek many cells ahead, so you "zoom out" to the block index level (or
> memstore root), whereas seek churns through every cell.
> Any help appreciated,
> Matt