use strict;
use Data::Dumper;

my $rowid = $ARGV[0] || 'roy';

my %data = ();
my @fields = split(/\t/, <DATA>);
chomp @fields;

while(<DATA>) {
    chomp;     
    my @row = split(/\t/);
    if ($row[0] eq $rowid) {
        @data{@fields} = @row;
        last;
    }        
}
 
if ( keys %data ) {
    # found, display data
    print Dumper \%data;
}
else {
    # not found, show error
    print STDERR "Can't find row '$rowid'\n";
}
 
__DATA__
rowid   course1 course2 course3 course4
marge   psychology  math    engineering pe
roy math    reading art cooking