This is what I mean by single-line conditionals

```
if ( !results.find{|lt| (listed_taxon['taxon_id'] == lt['taxon_id'] && lt['last_observation_id'] && lt['place_id'].nil? )} && (aggregator["#{listed_taxon['taxon_id']}"].nil? && (listed_taxon['last_observation_id'].nil?)) || ((!results.find{|lt| (lt['taxon_id']==listed_taxon['taxon_id'] && lt['place_id'].nil?) }) ))
```

That's pretty mystifying, and could be rewritten more clearly as

```
observed_listed_taxon_without_place_exists = results.find{|lt| listed_taxon['taxon_id'] == lt['taxon_id'] && lt['last_observation_id'] && lt['place_id'].nil?}
listed_taxon_without_place_exists = results.find{|lt| lt['taxon_id']==listed_taxon['taxon_id'] && lt['place_id'].nil? }
havent_added_this_listed_taxon_yet = aggregator["#{listed_taxon['taxon_id']}"].nil?
listed_taxon_not_observed = listed_taxon['last_observation_id'].nil?
if !observed_listed_taxon_without_place_exists && 
    havent_added_this_listed_taxon_yet && listed_taxon_not_observed || 
    !listed_taxon_without_place_exists
  # 'n stuff
end
```

Or something like that. I know this sounds nitpicky, but this isn't just a style thing. Other people will have to revisit this code eventually (probably me) so it helps to have the logic as readable as possible. It also helps me review your code. I would probably refactor in this way just to understand what's going on.

Regarding SQL, ok. This is a pretty niche tool, so I doubt it will see much use. If it becomes a problem I guess we can deal with it then