Comment 7 for bug 918056

There's no workaround because, afaik, this is the first reported case of this happening. It's generally not safe to workaround unless you understand why MySQL has chosen no index. If the table is small, maybe MySQL thinks it's faster to scan the whole table--and it could be correct.

I'm not sure yet if this a bug or the tool doing what it's supposed to. If you can easily reproduce this and provide PTDEBUG output, we could see if it's a bug. Else, the only workaround of sorts is to comment out the if block that starts like:

      if ( $self->{nibble} == 0 && !$self->{small_table} ) {
         my $explain_index = $self->__get_explain_index($sql);
         if ( lc($explain_index || '') ne lc($s->{index}) ) {
            die 'Cannot nibble table '.$q->quote($args{database}, $args{table})

I.e. prefix each line in that whole if { } block with #. At the moment, there's no easy way to implement an official workaround.