Replace nulls with a value in a file

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# 1  
Old 09-10-2013
Replace nulls with a value in a file


I've a PIPE delimited file with about 5 fields. Sometimes the records in the 4th field is null, so I want to replace it based on values we get it on 2nd field in the same file.

Following is an example.
ABCD|X-TYPE 3.0|2010|X-TYPE|20000
CDEF|C-TYPE 2.5|2011|C-TYPE|10000
XYZ|LX 4WD|2009|LX|20000
PQR|EX 4WD|2009||20000

on the 4th record, 4th field is null, so looking at its 2nd field value , I want to update the 4th field as EX. How can I do it using awk or sed.


Last edited by joeyg; 09-10-2013 at 03:54 PM.. Reason: Please wrap data and commands in CodeTags
# 2  
Old 09-10-2013
awk -F\| '$4=="" {$4=$2}1' OFS=\| file
ABCD|X-TYPE 3.0|2010|X-TYPE|20000
CDEF|C-TYPE 2.5|2011|C-TYPE|10000
XYZ|LX 4WD|2009|LX|20000
PQR|EX 4WD|2009|EX 4WD|20000

awk -F\| '$4=="" {split($2,a," ");$4=a[1]}1' OFS=\| file
ABCD|X-TYPE 3.0|2010|X-TYPE|20000
CDEF|C-TYPE 2.5|2011|C-TYPE|10000
XYZ|LX 4WD|2009|LX|20000
PQR|EX 4WD|2009|EX|20000

# 3  
Old 09-10-2013
Can we also do it at vi editor as we do global replacement? but using my scenario
# 4  
Old 09-10-2013
Why not use awk sed or a bash script?
My vi knowledge are limited and I try to avoid it Smilie
# 5  
Old 09-10-2013
sed version:
sed 's/\(\([^|]*|\)\{2\}\([^|]*|\)\{1\}\)|/\1\2/'

under vi, just current line:

under vi, all file:

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