Insert Header to CSV AWK and Bash version

AddHeaderToCSV.sh

# abc.csv contents
# Alpha, USA, 12
# Beta, USA, 13

# abc.csv contents after adding header
# Name, Country, Age
# Alpha, USA, 12
# Beta, USA, 13


#Using streams - Solution1
value=$(<abc.csv); echo "Name,Country,Age">abc.csv; echo "$value">>abc.csv

#Using streams - Solution2
echo -e "Name,Country,Age\n$(cat abc.csv)">abc.csv

#Using AWK
a=$( awk -F, 'NR==1 {print "Name","Country","Age"}{print $1,$2,$3}' abc.csv | column -t);echo "$a">abc.csv