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From William Slacum <wsla...@gmail.com>
Subject Re: total table rows
Date Mon, 09 Nov 2015 15:45:36 GMT
Pranked... you can't use a CountingIterator, because it can't be init'd.
Can we get rid of that limitation?

On Mon, Nov 9, 2015 at 10:43 AM, William Slacum <wslacum@gmail.com> wrote:

> An interator stack of FirstEntryInRowIterator + CountingIterator will
> return the count of rows in each tablet, which can then be combined on the
> client side.
>
> On Mon, Nov 9, 2015 at 10:25 AM, Josh Elser <josh.elser@gmail.com> wrote:
>
>> Yeah, there's no explicit tracking of all rows in Accumulo, you're stuck
>> with enumerating them (or explicitly tracking them yourself at ingest time).
>>
>> The easiest approach you can take is probably using the
>> FirstEntryInRowIterator and counting each row on the client-side.
>>
>> You could do another summation in a second iterator but this is a little
>> tricky to get correct. I tried to touch on this a little in a blog post[1].
>> If this is a one-off question you want to answer, doing the summation on
>> the client side is likely not to take excessively longer than a server-side
>> summation.
>>
>> [1]
>> https://blogs.apache.org/accumulo/entry/thinking_about_reads_over_accumulo
>>
>>
>> z11373 wrote:
>>
>>> I want to get total rows of a table (likely has more than 100M rows), I
>>> think
>>> to get that information, Accumulo would have to iterate all rows :-( This
>>> may not be typical Accumulo scenario.
>>>
>>> Is there a more efficient way to get total number of rows in a table?
>>> When Accumulo iterating those items, does it mean it will pull the data
>>> to
>>> the client? If yes, is there a way to ask it to return just the number,
>>> since that's the only data I care.
>>>
>>> Thanks,
>>> Z
>>>
>>>
>>>
>>> --
>>> View this message in context:
>>> http://apache-accumulo.1065345.n5.nabble.com/total-table-rows-tp15484.html
>>> Sent from the Developers mailing list archive at Nabble.com.
>>>
>>
>

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