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From Keith Turner <ke...@deenlo.com>
Subject Re: Directly addressing columnFamily/columnQualifiers results from a Scanner
Date Fri, 06 Jan 2012 18:42:38 GMT
The Accumulo implementation and API do not assume that Rows fit into
memory.  To work within this assumption, we usually iterate over data.
 I assume this HBase Result object sucks the row into a map in memory.
 We do not have anything like that.  In 1.4 we have the RowIterator,
which takes a scanner and makes it easy to iterate over the columns in
each row.  This may be helpful.

If you think we need something additional, open a ticket.

Keith

On Fri, Jan 6, 2012 at 11:09 AM, Michael Giordano
<MGiordano@netcentricinc.com> wrote:
> My apologies for the potentially silly question but I come from an HBase
> world and I am struggling to find equivalent functionality in Accumulo.
>
>
>
> In the HBase world, there is an object called "Result"
> (org.apache.hadoop.hbase.client.Result is the fully qualified name).
>
> The "Result" object is the product of iterating over a "ResultScanner"
> (org.apache.hadoop.hbase.client.ResultScanner is the fully qualified name).
>
> The "Result" object has a method called getValue(ColumnFamily,
> ColumnQualifier) which (unsurprisingly) gets the value associated with a
> ColumnFamily and ColumnQualifier.
>
>
>
> The cloudbase "Scanner" seems to be the equivalent to the HBase
> "ResultScanner" but I cannot seem to find an equivalent to the "Result"
> object.
>
>
>
> So I create a "Scanner" and call fetchColumn(columnFamily, columnQualifier)
> for several columnQualifiers.
>
> The way I get the data for a row is to iterate over all of the columns
> individually until I obtain all of the columnQualifiers I requested?
>
> Or is there a way to directly address the columnFamily/columnQualifer by
> name to obtain a value?
>
>
>
> Thanks for your anticipated support,
>
> Mike G.

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