I try to run the following code

use warnings;
use strict;
use autodie;

my $databas = "db";
my $password = "pass";
my $user = "postgres";

$dsn = "DBI:Pg:dbname = $database";
$dbh = DBI->connect($dsn, $user, $password, { RaiseError => 1 }) or di
+e "ERROR: The database could not be opened.";

create_table($dbh, $schema, $table, "col1 char(20)");

sub create_table {
    # my ($dbh, $schema, $table, $cols_type) = @_;
    my $dbh = $_[0];
    my $schema = "$_[1]";
    my $table = "$_[2]";
    my $cols_type = "$_[3]";

    $dbh->do("create table $schema.$table ($cols_type);");  # Hear it 
+happens; line 142
    return;
}
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It warns me: Use of uninitialized value $cols_type in concatenation (.) or string at ./test6.pl line 142. How can I prevent this error?