Nice work. Good to see the SQL code in there too! I'm getting to the point where I start reading other people's SQL to pick up tips! I hadn't seen .type before - that's useful.
Oh, arcange told me to use depth = 0 instead of parent_author = ''
I guess it's faster / more efficient.
ahh yes, and i read that comment too.
He said their was an index on that field, thanks for reminding me about it!