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HBase, mail # user - Is get a private case of scan ?


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Re: Is get a private case of scan ?
Amit Sela 2014-01-16, 07:23
I have a case where I want to "split" rows with a lot of qualifiers (a very
small amount of rows < 1%, with an exceptional number of qualifiers), into
a number of rows. Say like:
row1.....
row1_DELIMITER_UUID
row1_DELIMITER_UUID2
row2
I was thinking of using a postGet() RegionObserver (the "split" rows will
always be stored in the same region) but when digging into the code I
noticed that Get is a Scan so I was wondering why not just scan for all
row1s ?
On Wed, Jan 15, 2014 at 10:53 PM, Stack <[EMAIL PROTECTED]> wrote:

> On Wed, Jan 15, 2014 at 5:34 AM, Amit Sela <[EMAIL PROTECTED]> wrote:
>
> > Hi all,
> >
> > I was wondering if Get is implemented as a private case of scan ?
> > In HRegion, I see that the get passed is used to construct a Scan object
> > for the RegionScanner to use.
> >
> >
> A Get is a Scan, yes.
>
>
> > I was wondering if executing Scan(Get) vs Get from client api should have
> > any overhead ?
> >
>
> There are differences in that Get will pread from HDFS where Scan will seek
> and read under lock (and only fall back to pread when it notices contention
> on the hfile).
>
> Why do you want to Scan(Get) instead of Get?
>
> St.Ack
>