Adding to the above, Schönig's Mastering PostgreSQL 11 will help you advance from intermediate to high-intermediate PostgreSQL programmer, as will Faroult's The

Adding to the above, Schönig's Mastering PostgreSQL 11 will help you advance from intermediate to high-intermediate PostgreSQL programmer, as will Faroult's The Art of SQL. Karwin's SQL Antipatterns is useful supplementary reading also. I've looked through my kindle, and I wouldn't bother with much else.