How to extract only few lines of data from HDFS

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I've around 3 GB of data stored in HDFS. Can anyone tell me how do we get only a few lines of data.

This is how we do it in the Unix command line

cat sample.csv |head -n 100
I want the same thing to be done in case of hadoop but how to do it?

May 2, 2018 in Big Data Hadoop by kurt_cobain
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1 answer to this question.

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Here also in case of Hadoop, it is very similar to Unix, you can use the head parameter here as well as given below.

hadoop fs -cat /your/file | head
To get the tail there is another command in hadoop:

hadoop fs -tail /your/file
But, it returns last kilobyte of the data, not given number of lines.

Hope this will help!

answered May 2, 2018 by nitinrawat895
• 11,380 points

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