Useful Commands

Adding a header to an existing file:

echo -e "field1,field2,field3,field4,field5" | cat - test.csv > /tmp/tempFile && mv /tmp/tempFile test.csv

grep a file with wild card in the search string

grep "08/../2010" test.csv

Delete a line from a file matching a search string
sed -i.bak '/search string/d' file

Delete first line from the file
sed '1d' file.txt > tmpfile; mv tmpfile file.txt

Starting Hive session with Tez execution engine
hive --hiveconf hive.execution.engine=Tez 

Installing artifact into maven repository

mvn install:install-file -DgroupId=jdk.tools -DartifactId=jdk.tools -Dpackaging=jar -Dversion=1.6 -Dfile=tools.jar -DgeneratePom=true

 Installing Java 8 on centos

su -c "yum install java-1.8.0-openjdk"

 Updating JAVA_HOME

sudo gedit .bash_profile

Add JAVA_HOME=/usr/lib/jvm/java-1.8.0/jre

Update java -version

sudo vi .bashrc

Add PATH=/usr/lib/jvm/java-1.8.0/jre/bin:$PATH