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finding null records in data file

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# 1  
Old 01-09-2007
finding null records in data file

I am having a "|" delimited flat file and I have to pick up all the records with the 2nd field having null value. Please suggest.
# 2  
Old 01-09-2007
nawk -F'|' -v OFS='|' '!$2' myFile

# 3  
Old 01-09-2007
explain please


can u explain the code. I understood that we defined | as the delimiter but can u explain the remaining steps?

# 4  
Old 01-09-2007
nawk -F'|' -v OFS='|' '!$2' myFile

-F'|'        - define '|' as the INPUT field separator
-v OFS='|'   - define '|' as the OUTPUT field separator
'!$2'        - can be re-written as '$2 == ""' OR easier to understand '$2 == "" {print }'
               [all of which achieve the same].

Last edited by vgersh99; 01-09-2007 at 03:58 PM..

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