sub _new_schema {

    require Koha::Schema;

    my $context = C4::Context->new();

    my $db_driver = $context->{db_driver};

    my $db_name   = $context->config("database");
    my $db_host   = $context->config("hostname");
    my $db_port   = $context->config("port") || '';
    my $db_user   = $context->config("user");
    my $db_passwd = $context->config("pass");

    my ( %encoding_attr, $encoding_query, $tz_query, $sql_mode );
    my $tz = $ENV{TZ};
    if ( $db_driver eq 'mysql' ) {
        %encoding_attr = ( mysql_enable_utf8 => 1 );
        $encoding_query = "set NAMES 'utf8'";
        $tz_query = qq(SET time_zone = "$tz") if $tz;
        $sql_mode = "set sql_mode = ''";
    }
    elsif ( $db_driver eq 'Pg' ) {
        $encoding_query = "set client_encoding = 'UTF8';";
        $tz_query = qq(SET TIME ZONE = "$tz") if $tz;
    }
    my $schema = Koha::Schema->connect(
        {
            dsn => "dbi:$db_driver:database=$db_name;host=$db_host;port=$db_port",
            user => $db_user,
            password => $db_passwd,
            %encoding_attr,
            RaiseError => $ENV{DEBUG} ? 1 : 0,
            PrintError => 1,
            unsafe => 1,
            quote_names => 1,
            on_connect_do => [
                $encoding_query || (),
                $tz_query || (),
                $sql_mode || (),
            ]
        }
    );

    my $dbh = $schema->storage->dbh;
    eval {
        $dbh->{RaiseError} = 1;
        $dbh->do(q|
            SELECT * FROM systempreferences WHERE 1 = 0 |
        );
        $dbh->{RaiseError} = $ENV{DEBUG} ? 1 : 0;
    };
    $dbh->{RaiseError} = 0 if $@;

    return $schema;
}