FAQ
I have a large text file, approximately 500mb containing key value pairs on
each line. I would like to implement Hadoop MapFile so that I can access any
key,value pair fairly quickly. To construct either the Reader or Writer the
MapFile requires a Configurations object and a File System object. I am
confused as to how to create either object, and why they are necessary.
Would someone be so kind to demonstrate to me a trivial example as to how I
can accomplish this.

Thanks in advance.
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  • Amogh Vasekar at Apr 14, 2010 at 5:41 am
    Hi,
    The file system object will contain the scheme, authority etc for the given uri or path. The conf object acts as reference ( unable to get a better terminology ) to this info.
    Looking at the MapFileOutputFormat should help provide better understanding as to how writers and readers are initialized.

    Hope this helps,
    Amogh


    On 4/13/10 7:33 PM, "Placebo" wrote:



    I have a large text file, approximately 500mb containing key value pairs on
    each line. I would like to implement Hadoop MapFile so that I can access any
    key,value pair fairly quickly. To construct either the Reader or Writer the
    MapFile requires a Configurations object and a File System object. I am
    confused as to how to create either object, and why they are necessary.
    Would someone be so kind to demonstrate to me a trivial example as to how I
    can accomplish this.

    Thanks in advance.
    --
    View this message in context: http://old.nabble.com/How-do-I-use-MapFile-Reader-and-Writer-tp28230683p28230683.html
    Sent from the Hadoop core-user mailing list archive at Nabble.com.

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postedApr 13, '10 at 2:04p
activeApr 14, '10 at 5:41a
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