How to print a column using awk command line and add header

Question

I then run the following to target specific columns.
cat test1.txt | awk -F "|" '{ print $2, $3, $4, $6, $7}' > teste.csv

The CSV file outputs the result in 1 line like so:
column2 column3 column4 column6 column7

Would you be able to help me fix the above and  - also how can i then add headers after getting the correct result.
Thanks in advance

Bodo · Accepted Answer

If the problem is that the columns should be separated with | instead of space, you have to set the output field separator OFS to the same value as the input field separator FS.
awk -F "|" -v 'OFS=|' '{ print $2, $3, $4, $6, $7}' test1.txt > teste.csv

You can use the BEGIN condition to add commands for printing a header. In this case you also can put the assignement to OFS there.
awk -F "|" 'BEGIN { OFS=FS; print "header2|header3|header4|header6|header7" } { print $2, $3, $4, $6, $7}' test1.txt > teste.csv

Raman Sailopal · Answer

Given that you have referenced a csv (comma separated value output in your question), wit th sample data in the file columns, you can run:
awk -F| 'BEGIN { OFS=",";print "COLUMN1"OFS"COLUMN2"OFS"COLUMN3"OFS"COLUMN4"OFS"COLUMN5"OFS"COLUMN6"OFS"COLUMN7"OFS"COLUMN8"OFS } { $1=$1 }1' columns

Set the output to , in the BEGIN section and print the headers required (in the example COLUMN1,COLUMN2 etc) with the new OFS. Then take each line, set $1 to $1 to action a change on $0, taking account of the new OFS. Use 1 to print the new line.
Output:
COLUMN1,COLUMN2,COLUMN3,COLUMN4,COLUMN5,COLUMN6,COLUMN7,COLUMN8,
column1,column2,column3,column4,column5,column6,column7,column8,

Shaqil Ismail · Answer

To add the headers
awk 'BEGIN {print "Column1|Column2|Column3|Column4|Column5|Column6|Column7|Column8"} {print}' table > test1.txt
To add the columns you would like, into the teste.csv
cat test1.txt| awk -F '|' '{print $2, $3, $4, $6, $7}' > teste.csv

How to print a column using awk command line and add header

3 Answers

Add your own answers!

Ask a Question