Thanks for the tip! I didn't know EXISTS can provide such benefits. However, I've tried it out and it resulted in a 10x performance loss. Looking at the query

Thanks for the tip! I didn't know EXISTS can provide such benefits. However, I've tried it out and it resulted in a 10x performance loss. Looking at the query plan, it actually got PostgreSQL to be too smart and undo most of the optimizations I've done in this blog post... It's still an order of magnitude faster than the original query though!