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From Eric Newton <eric.new...@gmail.com>
Subject Re: Embedded Mutations: Is this kind of thing done?
Date Fri, 25 Apr 2014 13:30:02 GMT
I don't have detailed knowledge of your key, but generally speaking:

A row can have billions of columns.  There is no assumption in accumulo
that the row will fit in memory.  Of course, a single mutation will need to
fit in memory.

A row will always be served from just a single server, so its important to
have enough rows to spread the ingest/query load out over your cluster.

-Eric



On Fri, Apr 25, 2014 at 9:11 AM, Geoffry Roberts <threadedblue@gmail.com>wrote:

> Interesting, multiple mutations that is.  Are we talking multiples on the
> same row id?
>
> Upon reflection, I realized the embedded thing is nothing special.  I
> think I'll keep adding columns to a single mutation.  This will make for a
> wide row, but I'm not seeing that as a problem.  I am I being naive?
>
> Another question if I may.  As I walk my graph, I must keep track of the
> type of the value being persisted.  I am using the qualifier for this,
> putting in it a URI that indicates the type.  Is this a proper use for the
> qualifier?
>
> Thanks for the discussion
>
>
> On Thu, Apr 24, 2014 at 11:23 PM, William Slacum <
> wilhelm.von.cloud@accumulo.net> wrote:
>
>> Depending on your table schema, you'll probably want to translate an
>> object graph into multiple mutations.
>>
>>
>> On Thu, Apr 24, 2014 at 8:40 PM, David Medinets <david.medinets@gmail.com
>> > wrote:
>>
>>> If the sub-document changes, you'll need to search the values of every
>>> Accumulo entry?
>>>
>>>
>>> On Thu, Apr 24, 2014 at 5:31 PM, Geoffry Roberts <threadedblue@gmail.com
>>> > wrote:
>>>
>>>> The use case is, I am walking a complex object graph and persisting
>>>> what I find there.  Said object graph in my case is always EMF (eclipse
>>>> modeling framework) compliant.  An EMF graph can have in if references
>>>> to--brace yourself--a non-cross document containment reference.  When using
>>>> Mongo, these were persisted as a DBObject embedded into a containing
>>>> DBObject.  I'm trying to decide whether I want to follow suit.
>>>>
>>>> Any thoughts?
>>>>
>>>>
>>>> On Thu, Apr 24, 2014 at 4:03 PM, Sean Busbey <busbey@cloudera.com>wrote:
>>>>
>>>>> Can you describe the use case more? Do you know what the purpose for
>>>>> the embedded changes are?
>>>>>
>>>>>
>>>>> On Thu, Apr 24, 2014 at 2:59 PM, Geoffry Roberts <
>>>>> threadedblue@gmail.com> wrote:
>>>>>
>>>>>> All,
>>>>>>
>>>>>> I am in the throws of converting some(else's) code from MongoDB to
>>>>>> Accumulo.  I am seeing a situation where one DBObject if being embedded
>>>>>> into another DBObject.  I see that Mutation supports a method called
>>>>>> getRow()  that returns a byte array.  I gather I can use this to
achieve a
>>>>>> similar result if I were so inclined.
>>>>>>
>>>>>> Am I so inclined?  i.e. Is this the way we do things in Accumulo?
>>>>>>
>>>>>> DBObject, roughly speaking, is Mongo's counterpart to Mutation.
>>>>>>
>>>>>> Thanks mucho
>>>>>>
>>>>>> --
>>>>>> There are ways and there are ways,
>>>>>>
>>>>>> Geoffry Roberts
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Sean
>>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> There are ways and there are ways,
>>>>
>>>> Geoffry Roberts
>>>>
>>>
>>>
>>
>
>
> --
> There are ways and there are ways,
>
> Geoffry Roberts
>

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