Magnus Hagander <magnus@hagander.net> writes:
> As Amit mentions it is also triggered by some store parameter changes. But
> not all. So looking at it the other way, the part that the end user really
> cares about it "which ALTER TABLE operations will rewrite the table and
> which will not". Maybe what we need is a section specifically on this that
> summarizes all the different ways that it can happen.
No, what we need is EXPLAIN for DDL ;-). Trying to keep such
documentation in sync with the actual code behavior would be impossible.
(For one thing, some aspects can be affected by extension datatype
behaviors.)
regards, tom lane