How to make a strict match with awk-CodePudding

I am querying one file with the other file and have them as following:

File1:

Angela S Darvill| text text text text   
Helen Stanley| text text text text   
Carol Haigh S|text text text text .....

File2:

Carol Haigh  
Helen Stanley  
Angela Darvill

This command:

awk 'NR==FNR{_[$1];next} ($1 in _)' File2.txt File1.txt

returns lines that overlap, BUT doesn’t have a strict match. Having a strict match, only Helen Stanley should have been returned.

How do you restrict awk on a strict overlap?

CodePudding user response：

With your shown samples please try following. You were on right track, you need to do 2 things, 1st: take whole line as an index in array a while reading file2.txt and set field seapeator to | before awk starts reading file1

awk -F'|' 'NR==FNR{a[$0];next} $1 in a' File2.txt File1.txt

CodePudding user response：

You can also use grep to match from File2.txt as a list of regexes to make an exact match.

You can use sed to prepare the matches. Here is an example:

sed -E 's/[ \t]*$//; s/^(.*)$/^\1|/' File2.txt
^Carol Haigh|
^Helen Stanley|
^Angela Darvill|
...

Then use process with that sed as an -f argument to grep:

grep -f <(sed -E 's/[ \t]*$//; s/^(.*)$/^\1|/' File2.txt) File1.txt
Helen Stanley| text text text text

Since your example File2.txt has trailing spaces, the sed has s/[ \t]*$//; as the first substitution. If your actual file does not have those trading spaces, you can do:

grep -f <(sed -E 's/.*/^&|/' File2.txt) File1.txt