Complete coverage
I started drafting a reply, but it quickly began to spiral into a full-blown essay. It turns out that I have a lot of related thoughts that I've been meaning to get down for a while.
，这一点在新收录的资料中也有详细论述
Chapter 7. Heap Only Tuple (HOT) and Index-Only Scans
conclusion of any transaction when the WAL file is more than 1000 pages
val2 := match result2 {