Luca Ferrari <fluca1978@gmail.com> writes:
> I've a doubt about running ANALYZE and inspecting pg_class.xmin and
> pg_class.reltuples.
> ...
> So the pg_class record has changed its content, and in fact we are now
> 2 transaction away the table creation, but the pg_class.xmin is the
> same.
ANALYZE (and VACUUM) update the table's pg_class row non-transactionally.
See the comments for vac_update_relstats():
https://git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/backend/commands/vacuum.c;h=5c4bc15b441b36da99b0703500a3268086b40d9e;hb=HEAD#l1266
regards, tom lane