Well you didn't say what you want to do with the results, but assuming you want them in an Array of Arrays: 
use DBI;
my $dbh=DBI->connect('dbi:CSV(RaiseError=1):');
my $results = $dbh->selectall_arrayref("
    SELECT * FROM file1 NATURAL JOIN file2
");

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In reply to Re: Joining two files on common field by jZed
in thread Joining two files on common field by ch1

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