So I need to either find an Index that will work with regexes or re-write my code to update each subdirectory separately and use simpler UPDATE statement for each.
Why don't you use a LTREE type to model your directory tree ? It's been designed specifically for this purpose and has indexed regular expression search.
http://www.sai.msu.su/~megera/postgres/gist/ltree/ http://www.sai.msu.su/~megera/postgres/gist/
---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend
