split string awk examples

Example 1: bash split string with awk

# Basic syntax:
awk '{split($column_to_split,array_name,"delimiter"); print a[index]}'
# Where:
#	- the array_name is usually shortened to a
#	- delimiter is the delimiter you want to split the string by
#	- index is the index of the string "piece" you want to work with

# Example usage:
# Say you want to split the following string by underscores and print
# the third item:
string_containing_CODE_to_pentagon
echo "string_containing_CODE_to_pentagon" | awk '{split($0,a,"_"); print a[3]}'
--> CODE

# Example usage:
# Say you have input_file.txt that contains two columns and you want to 
# split the second column by | and then by _ and then print the second 
# string of the final split:
cat file.txt
--> code_1	12|ab_cd|34_ef
	code_2	ef_56|gh_78_ij

awk '{split($2, a, "|");  split(a[2],b,"_"); print b[2]}' file.txt
--> cd
	78

Example 2: awk define string as delimiter

Just use function split in awk command to split a line into an array 'a'
using a choosen string as delimiter as for example ", " in next use case:
echo "hi, bye, hey" | awk '{split($0,a,", "); print a[3],a[2],a[1]}'