remove row if string is same as previous row


 
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# 1  
Old 06-10-2010
remove row if string is same as previous row

I have data like:

Blue Apple 6
Red Apple 7
Yellow Apple 8
Green Banana 2
Purple Banana 8
Orange Pear 11


What I want to do is if $2 in a row is the same as $2 in the previous row remove that row. An identical $2 may exist more than one time.

So the out file would look like:

Blue Apple 6
Green Banana 2
Orange Pear 11


I'm new and don't really have any idea about the type of code that would work or if this would require something like Perl.

Thank you for your help.
# 2  
Old 06-10-2010
Code:
awk 'NR==1{x=$2;print;next}{if (x==$2){next} else {x=$2;print}}' infile

This User Gave Thanks to bartus11 For This Post:
# 3  
Old 06-10-2010
Here you go:
Code:
$ cat bla.txt
Blue Apple 6
Red Apple 7
Yellow Apple 8
Green Banana 2
Purple Banana 8
Orange Pear 11
$ awk '$2 != prev{print; prev=$2;}' bla.txt
Blue Apple 6
Green Banana 2
Orange Pear 11

# 4  
Old 06-10-2010
Thanks so much all it looks great. Smilie
# 5  
Old 06-10-2010
Code:
awk '!a[$2]++' file

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