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From Adam Fuchs <>
Subject Re: Unicode
Date Thu, 03 May 2012 19:04:27 GMT
Hi Ralph,

Accumulo itself doesn't do any normalization or encoding. Everything looks
like byte arrays to Accumulo. The Accumulo shell will output unprintable
characters using the \xXX, where the XX is the hex encoding of the given
byte. This is probably what you are seeing. The WikiSearch application
includes a bunch of code to parse wikipedia files and canonicalize the
encoding of data into unicode before ingesting into Accumulo. That code is
mostly in
the src/examples/wikisearch/ingest/src/main/java/org/apache/accumulo/examples/wikisearch/normalizer
directory. The WikiSearch approach is certainly good enough for a
demonstration, but this is a big area where a lot of people have done a lot
of work, and we certainly don't try to recreate that within Accumulo. One
other place to look is Lucene for tokenization and normalization libraries.


On Thu, May 3, 2012 at 1:30 PM, Perko, Ralph J <> wrote:

> The formatting got lost in the example - there is supposed to be a dash
> (-) between 1975 and 76.
> On 5/3/12 10:21 AM, "Perko, Ralph J" <> wrote:
> >Hi ­ I have some questions regarding accumulo and unicode.
> >
> >I'm working with the wikisearch example:
> >
> >Given some article such as: 1975­76 ...
> >
> >I see in the Wiki example that the title is normalized and becomes encoded
> >as 1975\xE2\x80\x9376
> >But if I ingest that same data myself and do not use the Normalizer I get
> >the same title that the normalizer produced.  Likewise, if I insert the
> >wikipedia data as plain XML and not base64 encoded, I see the same thing,
> >specifically where articles link to other languages.  The language
> >characters are normalized.
> >
> >Does accumulo normalize automatically?  Am I misunderstanding what I am
> >seeing?  What is the general guidance for using accumulo with Unicode
> >characters?
> >
> >Thanks,
> >Ralph
> >
> >
> >

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