Shell Programming and Scripting

Hi,

I have two huge file; each one has approximately 150000 lines. I need to compare both of them and store the unmatched lines into a different file.

I have searched for everything in google but did not get solution.

Files are:
File1

Code:

NRALBAMINDB20003726
NRALBAMINDB20003727
NRALBAMINDB20003728

File2

Code:

NRALBAMINDB20003726
NRALBAMINDB20003727
NRALBAMINDB20003733

Output:

Code:

NRALBAMINDB20003728

I have tried the below query -

Code:

awk 'FILENAME=="File2" {arr[$0]++}
FILENAME=="File1" {If ($0 in arr) {continue}
else {print $0}}' File2 File1 >File3.txt

But its not working, output I am getting is - complete file1 gets pasted in File3 that is 'if part' is not getting executed.

One more thing, If i try the code with pretty less no of entries in File1 and File2 say 20 entries each, it works.

Thanks,
Suman.

Welcome to the forum!

Since it is just 150000 lines, it is not huge.

Code:

diff file1 file2 | grep '^<'|sed 's/^< //'

will be much faster

What makes you think this is much faster?

If both files are sorted, then:

Code:

comm -23 file1 file2

Thanks to every one.

But i just want to know why the code which i implemented did not work.



Thanks,
Suman