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Accumulo, mail # user - Key length limitations


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Re: Key length limitations
Christopher 2014-01-26, 22:32
Yes, I mean the row, column family, column qualifier (and also column
visibility).
I had intended "each", not "total", because 1K is probably too
constraining for some applications, but I don't think you'd see any
significant difference between the two, as they are on the same order
of magnitude.

--
Christopher L Tubbs II
http://gravatar.com/ctubbsii
On Sun, Jan 26, 2014 at 8:11 AM, Jamie Johnson <[EMAIL PROTECTED]> wrote:
> Sorry for the basic question, but by key segment do you mean row key, column
> family column qualifier?  So each should be less than a kilobyte or total?
> I think either way we are below that but I just want to make sure I
> understand the terminology.  Again thanks for the reply.
>
>
> On Sun, Jan 26, 2014 at 2:12 AM, Christopher <[EMAIL PROTECTED]> wrote:
>>
>> On the order of a kilobyte, or less, per key segment is probably
>> ideal. Beyond that, you may want to experiment to see what works for
>> you.
>>
>> Up to the order of a megabyte may work fine in newer versions (at
>> least 1.4), but I'd start having concerns about your schema decisions
>> after that, even if your performance was fine... since ultimately,
>> Accumulo tables are a sorted index, and I'd wonder what kind of index
>> needs such large keys.
>>
>> I suspect a few hundred bytes is probably plenty for most applications.
>>
>> --
>> Christopher L Tubbs II
>> http://gravatar.com/ctubbsii
>>
>>
>> On Sat, Jan 25, 2014 at 9:06 AM, Jamie Johnson <[EMAIL PROTECTED]> wrote:
>> > I've read that in HBase there is a recommended limit on key lengths
>> > because
>> > they're passed around quite a bit. Is the same true of accumulo?  Are
>> > there
>> > any recommendations in this regard?
>
>