To all the upvoters, did you actually read the linked slides or are you just upvoting because it has "PostgreSQL" in the name[1]? Interesting to see this many votes with zero comments.

It is a great set of slides by the way. The btree piece would be old news to anyone familiar with database related data structures but the detail on GIN, GIST, and particularly BRIN make for a good read. Seeing the physical layout for each of those gives you a much better understanding of the cost of maintenance and what situations would they'd be useful.

Also, if you happened to follow the recent Postgres/Uber thread, this gives a lot more context as to how updates to a row would cascade to many writes for each index.

[1]: ... which isn't a bad idea anyway because PostgreSQL is awesome!