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How to use awk for deleting columns?

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Top Forums Shell Programming and Scripting How to use awk for deleting columns?
# 1  
Old 07-10-2012
How to use awk for deleting columns?
Hi folks,

How awk 'll help to do this file contains bunch of insert statement like below remove fourth column from all statement put it in new file

Code:
INSERT INTO `tbl_medicalquestions` VALUES (1,'Is anyone waiting for an operation, post operative check up, any other hospital treatment or any medical investigations, tests or test results (for anything other than pregnancy)?',0,0,'2010-10-19 11:44:44');


Moderator's Comments:
Mod Comment Please use code tags next time for your code and data.
Last edited by Scrutinizer; 07-11-2012 at 03:20 AM.. Reason: code tags, see PM
# 2  
Old 07-10-2012
What is the column that you are talking about? Smilie
# 3  
Old 07-11-2012
if you check the insert statement ----)?',0,0 second zero stand for the fourth column like this I have to delete it

---------- Post updated 07-11-12 at 12:23 AM ---------- Previous update was 07-10-12 at 09:25 PM ----------

Problem of deleting columns from insert statements...can you help me out
# 4  
Old 07-11-2012
Code:
 
awk -F"\'," -v OFS="\'," '{sub(/,.*,/,",",$2)}1' input.txt

This User Gave Thanks to itkamaraj For This Post:
ashutoshverma
# 5  
Old 07-11-2012
Try:
Code:
awk '{$(NF-1)=$NF; NF--}1' FS=, OFS=, infile

--
or
Code:
awk '$NF=$(NF--)' FS=, OFS=, infile

Smilie
Last edited by Scrutinizer; 07-11-2012 at 03:37 AM..
This User Gave Thanks to Scrutinizer For This Post:
ashutoshverma
# 6  
Old 07-11-2012
sorry back again I ran this command I only want to delete fourth column from this insert statement (INSERT INTO `tbl_medicalquestions` VALUES ) there are other insert statements too in the file which I don't want to delete
grep '`tbl_medicalquestions`' insert_script20120711.txt | awk -F"\'," -v OFS="\'," '{sub(/,.*,/,",",$2)}1' insert_script20120711.txt > insert_scriptold.txt

---------- Post updated at 06:48 AM ---------- Previous update was at 06:22 AM ----------

Any one can help me out please....
# 7  
Old 07-11-2012
How about this, then?
Code:
 
awk -F"\'," -v OFS="\'," '/tbl_medicalquestions/ {sub(/,.*,/,",",$2)}1' input.txt

This User Gave Thanks to Corona688 For This Post:
ashutoshverma
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