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From Keith Turner <>
Subject Re: Is there a sensible way to do this? Sequential Batch Scanner
Date Wed, 28 Oct 2015 15:04:28 GMT
Will the results always fit into memory?  If so could put results from
batch scanner into ArrayList and sort it.

On Tue, Oct 27, 2015 at 6:21 PM, Rob Povey <> wrote:

> What I want is something that behaves like a BatchScanner (I.e. Takes a
> collection of Ranges in a single RPC), but preserves the scan ordering.
> I understand this would greatly impact performance, but in my case I can
> manually partition my request on the client, and send one request per
> tablet.
> I can’t use scanners, because in some cases I have 10’s of thousands of
> none consecutive ranges.
> If I use a single threaded BatchScanner, and only request data from a
> single Tablet, am I guaranteed ordering?
> This appears to work correctly in my small tests (albeit slower than a
> single 1 thread Batch scanner call), but I don’t really want to have to
> rely on it if the semantic isn’t guaranteed.
> If not Is there another “efficient” way to do this.
> Thanks
> Rob Povey

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