Two files comparision with single field

Shell Programming and Scripting
1

Hi ,

Im new to uxin environment and shell scripting....

please help me with the code for the following scenario.....

file 1 contains the following fields

abc 200 rupee IND
cdf  400 dollar USA
efg  300 euro  GER
 hij  600 pound ENG

file 2

SBI abc 321 dollar CANAD
kvr mnd  345 pound FRANC
axs efg  879 euro   RUSSIA

if field 1 of file1 matches field 2 of file2 then complete row of filed2 in file should be displayed.

output file:

SBI abc 321 dollar CANAD
axs efg 879 euro RUSSIA

Can someone help on this ....

2 
awk 'NR==FNR{a[$1]++;next}a[$2]' file1 file2
3

thanks for the reply...

im getting the below error ..

 
$ awk 'NR==FNR{a[$1]++;next}a[$2]' f1.dat_old f2.dat_old
awk: syntax error near line 1
awk: bailing out near line 1

please let me know how to resolve.

thanks
Shivaji...

4

On Solaris use /usr/xpg4/bin/awk rather than awk

--
@pravin27
It is better to use

$2 in a

instead of

a[$2]

Because otherwise awk will create a new element a[$2] for every line in the second file.

5

thanks.....its working :slight_smile:

6

would you please explain the login in the syntax "

{a[$1]++;next}a[$2]

"

thanks
Shivaji

7

Hi.

Assuming that the files are standardized to have fields separated by single spaces, then here are 2 alternate solutions:

#!/usr/bin/env bash

# @(#) s1	Demonstrate extraction by matching fields.

# Utility functions: print-as-echo, print-line-with-visual-space, debug.
# export PATH="/usr/local/bin:/usr/bin:/bin"
pe() { for _i;do printf "%s" "$_i";done; printf "\n"; }
pl() { pe;pe "-----" ;pe "$*"; }
db() { ( printf " db, ";for _i;do printf "%s" "$_i";done;printf "\n" ) >&2 ; }
db() { : ; }
C=$HOME/bin/context && [ -f $C ] && $C cut fgrep join

FILES="data?"

pl " Input data file $FILES:"
head $FILES

pl " Results, grep:"
fgrep -f <(cut -f1 -d" " data1) data2

pl " Results, join:"
sort -t " " --key=1,1 data1 > f1
sort -t " " --key=2,2 data2 > f2
join -1 1 -2 2 -t " " -o 2.1,2.2,2.3,2.4,2.5 f1 f2
rm -f f1 f2

exit 0

prodiucing:

% ./s1

Environment: LC_ALL = C, LANG = C
(Versions displayed with local utility "version")
OS, ker|rel, machine: Linux, 2.6.26-2-amd64, x86_64
Distribution        : Debian GNU/Linux 5.0.8 (lenny) 
bash GNU bash 3.2.39
cut (GNU coreutils) 6.10
fgrep GNU grep 2.5.3
join (GNU coreutils) 6.10

-----
 Input data file data?:
==> data1 <==
abc 200 rupee IND
cdf 400 dollar USA
efg 300 euro GER
hij 600 pound ENG

==> data2 <==
SBI abc 321 dollar CANAD
kvr mnd 345 pound FRANC
axs efg 879 euro RUSSIA

-----
 Results, grep:
SBI abc 321 dollar CANAD
axs efg 879 euro RUSSIA

-----
 Results, join:
SBI abc 321 dollar CANAD
axs efg 879 euro RUSSIA

See man pages for details.

Best wishes ... cheers, drl