sub table_exists {
    my ($dbh, $table, $schema) = @_;

    unless ($schema) {
        ($schema) = $dbh->selectrow_array('SELECT DATABASE()');
    }

    my ($exists) = $dbh->selectrow_array(
        "SELECT COUNT(*) FROM information_schema.tables WHERE table_schema = ? AND table_name = ?",
        undef, $schema, $table,
    );

    return $exists > 0;
}