> That is not a true clustered index or index organized table, the table is still a heap and there is still a secondary index that is the b-tree. Fair point.

> That is not a true clustered index or index organized table, the table is still a heap and there is still a secondary index that is the b-tree. Fair point. The speed increase is still decent [0], although if you don't need most of the tuples (and ignoring TOAST-ed columns), you could achieve similar results with a simple REINDEX. > Since most of your key are indexed typically this is an issue either way since that will cause fragmentation in clustered or non clustered indexes on a random UUID requiring page splits etc. Agreed. I keep trying to convince Postgres fanboys that it matters, to relatively little success. I think the tide is slowly turning as "thought leaders" have begun publishing blog posts on this. [0]: https://gist.github.com/stephanGarland/0ba0d6348ca0dedae8b4c2269f2b3eb9 https://gist.github.com/stephanGarland/0ba0d6348ca0dedae8b4c...