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Accumulo >> mail # user >> XML Storage - Accumulo or HDFS

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Re: XML Storage - Accumulo or HDFS
There are advantages to using Accumulo to store the contents of your
XML documents, depending on their structure and what you want to end
up taking out of them. Are you trying to emulate the document store
pattern that the Wikipedia example uses?

On Wed, Jun 6, 2012 at 4:20 PM, Perko, Ralph J <[EMAIL PROTECTED]> wrote:
> Hi,  I am working with large chunks of XML, anywhere from 1 – 50 GB each.  I am running several different MapReduce jobs on the XML to pull out various pieces of data, do analytics, etc.  I am using an XML input type based on the WikipediaInputFormat from the examples.  What I have been doing is 1) loading the entire XML into HDFS as a single document 2) parsing the XML on some tag <foo> and storing each one of these instances as the content of a new row in Accumulo, using the name of the instance as the row id.  I then run other MR jobs that scan this table, pull out and parse the XML and do whatever I need to do with the data.
> My question is, is there any advantage to storing the XML in Accumulo versus just leaving it in HDFS and parsing it from there?  Either as a large block of XML or as individual chunks, perhaps  using Hadoop Archive to handle the small-file problem?  The actual XML will not be queried in and of itself but is part other analysis processes.
> Thanks,
> Ralph
> __________________________________________________
> Ralph Perko
> Pacific Northwest National Laboratory