How to extract only few lines of data from HDFS

Question

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?

Answer 1

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!