UNIX for Dummies Questions & Answers

Hello I am a new unix user, and I have a work related task to compare 2 files and print all of the lines in file 2 that contain a string from file 1 Note: the fields are in different columns in the files. I suspect the is a good use for awk? Thanks for your time & help

File 1

123 232 W343
321 323 W454
999 666 W777

File 2

333 W343 989
577 W323 979
888 W777 555

Result =

333 W343 989
888 W777 555

This does a couple loops per line in file2, could be optimized maybe if more was known?

Code:

[mute@geek ~/test]$ awk 'NR == FNR { a[$0]++ } NR != FNR { for (e in a) for (i=1;i<NF;i++) if (e ~ $i) print $0 }' file1 file2
333 W343 989
888 W777 555

Scott,
Thanks! I am anxious to try your solution, here is a litte more of the story, we have a large file of errors related to all parts, (File2 in my example) I am trying to filter that file & find only the errors related to parts in a specific product (File1) the common denominator between the 2 files is something called the work order number. this work order number is found in both files, the files are .csv files

so.......

My ideal script or program would search for the list of work orders in file1, then filter file2(The large file) for the lines containing the corresponding work orders, then create a 3rd file containing the result that could be printed so that we can fix the errors related to a specific product,this will enable us to prioritze the parts to be fixed.

I hope this helps
Thanks again!

Then we can create an array containing just the work order #, if I knew how to extract it from file1.

Is it in every row, and is it same column each row? if you can make quick sample of each file replacing confidential parts with fake data would help.

Scott I am @ home so I dont have access to the file but I can answer your questions, the work order is in a consistant field in both files, although I believe its in different fields (for example in file1 I beleve its field 5 in file2 I believe its field 3) also both files will always contain a work order number. sorry I cant provide the file today

Thanks again

P.S. I am anxious to learn any reccomended books for the beginner?

I do not know book. I have done some C and awk is easy after referencing manual at The AWK Manual - Table of Contents

Is ok you don't have sample but knowing they are both csv just with different column we can use like:

Code:

awk -F',' 'NR == FNR { a[$5]++ } NR != FNR && a[$3]' file1 file2

NR is record number, by default a record is a line. FNR is file record number, thus, for the first file the two are the same. When file2 is opened, NR keeps incrementing, but FNR resets. So they are equal for file1 and we put the 5th field into associative array. So a[workorder#] is counting them... Then the expression is a[$3] for file2, to see if that key exists from file1 and the default action is to print the line...

So hopefully you only need to change the 5 and 3 for this to work.

Thanks again Scott,

I am actually looking forward to work on Monday so that I can take your solution out for a test drive. I really appreciate your insights and I will let you know how it goes

Take care
Kevin