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From Josh Elser <josh.el...@gmail.com>
Subject Re: Embedded Mutations: Is this kind of thing done?
Date Fri, 25 Apr 2014 14:17:31 GMT
Not necessarily. If you are storing just the type in the colq and have 
one value and type per document/row, you won't have a problem. If you 
have more than one value in a type per document/row, the last one you 
inserted will be what sticks (which is likely undesirable).

Of course, this is also assuming there isn't some other uniquely 
identifying attribute in the colfam.

On 4/25/14, 9:55 AM, Geoffry Roberts wrote:
> Thanks for the comments.
>
> I'm using the qualifier to tell me the type of the value.  Sounds like
> I'm misusing it.
>
> My EMF documents are running  no more than 5k so I gather a row will fit
> into memory well enough.
>
>
> On Fri, Apr 25, 2014 at 9:29 AM, Mike Drob <madrob@cloudera.com
> <mailto:madrob@cloudera.com>> wrote:
>
>     Large rows are only an issue if you are going to try to put the
>     entire row in memory at once. As long as you have small enough
>     entries in the row, and can treat them individually, you should be fine.
>
>     The qualifier is anything that you want to use to determine
>     uniqueness across keys. So yes, this sounds fine, although possibly
>     not fine grain enough.
>
>     Mike
>
>
>     On Fri, Apr 25, 2014 at 9:11 AM, Geoffry Roberts
>     <threadedblue@gmail.com <mailto: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
>         <mailto: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 <mailto: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 <mailto: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 <mailto: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
>                         <mailto: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
>
>
>
>
>
> --
> There are ways and there are ways,
>
> Geoffry Roberts

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