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From Corey Nolet <cjno...@gmail.com>
Subject Re: Retrieving Rows in Reverse (Descending) Order
Date Mon, 30 Jun 2014 17:25:48 GMT
Donald,

Thanks for the share! Awhile ago, I stumbled across leveldb and I also
pondered the ability to support reverse scanning as a first class feature
in Accumulo. The numbers on that ticket are not surprising, however- we'd
have to assume there'd be a trade-off to make. The trade-off between ingest
throughput and total space consumed vs higher query latency may very well
be worth it for many use cases.

+1 for filing a ticket.



On Mon, Jun 30, 2014 at 12:52 PM, Donald Miner <dminer@clearedgeit.com>
wrote:

> Looks like it was easier said than done for HBase, but they did it:
> https://issues.apache.org/jira/browse/HBASE-4811
>
>
>
>
> On Mon, Jun 30, 2014 at 12:46 PM, Andrew Wells <awells@clearedgeit.com>
> wrote:
>
>> so, if you need to do both, ascending and descending order. I would need
>> to do 2 writes for each record going in... that might not be possible in
>> our situation.
>>
>>
>> On Mon, Jun 30, 2014 at 12:26 PM, Corey Nolet <cjnolet@gmail.com> wrote:
>>
>>> Andrew,
>>>
>>> Our recommendation on this has typically been to reverse the sort order
>>> of the keys on ingest.
>>>
>>>
>>> On Mon, Jun 30, 2014 at 12:24 PM, Andrew Wells <awells@clearedgeit.com>
>>> wrote:
>>>
>>>> Are there currently any good practices on doing this?
>>>>
>>>> Especially when a rowId has a large number of Keys.
>>>>
>>>> --
>>>> *Andrew George Wells*
>>>> *Software Engineer*
>>>> *awells@clearedgeit.com <awells@clearedgeit.com>*
>>>>
>>>>
>>>
>>
>>
>> --
>> *Andrew George Wells*
>> *Software Engineer*
>> *awells@clearedgeit.com <awells@clearedgeit.com>*
>>
>>
>
>
> --
>
> Donald Miner
> Chief Technology Officer
> ClearEdge IT Solutions, LLC
> Cell: 443 799 7807
> www.clearedgeit.com
>

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