sub _debug_query {
    my ($sql, @values) = @_;

    # Format query
    $sql =~ s/(FROM|(LEFT )?JOIN|WHERE|AND|GROUP|ORDER|LIMIT)/\n$1/g;
    $sql =~ s/(SELECT|ROWS)/$1\n/g;
    $sql =~ s/(\w{4,},)/$1\n/g;

    # Replace values
    @values = map { $_ =~ m/^\d+$/ ? $_ : "'$_'" } @values;
    $sql =~ s/\?/shift @values/e while (@values);

    warn "$sql\n";
}