I am trying to sharpen my understanding of Postgres. As I understand, Postgres does not write directly to disk blocks. It uses the file system provided by the OS:
My question: How can it then store a B Tree on disk? I would think storing a B Tree requires storing disk offset addresses and so on (for a node to navigate to another etc.). For this, one would need to write directly to the disk using low-level disk access functions and not use file system API.
