Perl: Accept User Input in if-else statement
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I am accepting User Input in an If-Else block. Check Code:

    if($svr==1) {
    print "Enter Datbase Name\n";
    my $db=<>;
    chomp($db);
    } elsif($svr==2) {
    print "Enter Data Source Name (DSN)\n";
    my $db=<>;
    chomp($db);
    }

When I am referring to $db in a later statement, I am getting the following error:

"Use of uninitialized value $db"

This is the statement in which I am using $db that is  causing the error:

    my $data_source = 'DBI:mysql:' . $db . ':' . $host;

Please help