On 04.04.22 01:58, David G. Johnston wrote:
> "Because pg_dump is used to transfer data to newer versions of
> PostgreSQL, the output of pg_dump can be expected to load into
> PostgreSQL server versions newer than pg_dump's version." [1]
>
> That is what I'm getting on about when talking about migrations. So a
> v14 SQL backup produced by a v14 pg_dump restored by a v15 psql.
It has always been the case that if you want the best upgrade
experience, you need to use the pg_dump that is >= server version.
The above quote is a corollary to that we don't want to gratuitously
break SQL syntax compatibility. But I don't think that implies that the
behavior of those commands cannot change at all. Otherwise we could
never add new behavior with new defaults.