As I am in a good mood, I have cobbled together a quick example.

Given these two CSV-files:

file1

key1,key2,data1,data2,data3
A,1,A1d1,A1d2,A1d3
A,2,A2d1,A2d2,A2d3
B,1,B1d1,B1d2,B1d3

[download]
and file2
key1,key2,data4,data5
A,1,A1d4,A1d5
A,2,A2d4,A2d5
B,1,B1d4,B1d5
A,2,A2d4bis,A2d5bis
A,2,A2d4ter,A2d5ter
B,1,B1d4bis,B1d5bis

[download]
The following program combines the matching lines from both files: 
use strict;
use warnings;
use 5.012;

use DBD::CSV;

my $dbh =
  DBI->connect( "dbi:CSV:f_dir=.", undef, undef,
    { FetchHashKeyName => "NAME_lc", RaiseError => 1, PrintError => 1,
+ } )
  or die $DBI::errstr;

my $query =
'SELECT key1, key2, data1, data2, data3, data4, data5 FROM file1 JOIN 
+file2 WHERE file1.key1 = file2.key1 AND file1.key2 = file2.key2';
my $sth = $dbh->prepare($query);
$sth->execute();
while ( my @row = $sth->fetchrow_array ) {
    say join '|', @row;
}
$sth->finish();

[download]
Output:
A|1|A1d1|A1d2|A1d3|A1d4|A1d5
A|2|A2d1|A2d2|A2d3|A2d4|A2d5
A|2|A2d1|A2d2|A2d3|A2d4bis|A2d5bis
A|2|A2d1|A2d2|A2d3|A2d4ter|A2d5ter
B|1|B1d1|B1d2|B1d3|B1d4|B1d5
B|1|B1d1|B1d2|B1d3|B1d4bis|B1d5bis

[download]

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

In reply to Re: Compare Two Text Files Based on a String by CountZero
in thread Compare Two Text Files Based on a String by Anonymous Monk

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