In the spirit of "asking the question leads you to the answer", while
ANALYZE doesn't update stats on toast tables, VACUUM does. So running
VACUUM ANALYZE on the parent table updates all the relevant "relpages"
slots and the space summary turns out passable guesstimates.
P.
On Fri, Aug 28, 2015 a
I've been trying to write up a "pg_total_relation_size()" replacement
that just uses the system tables (sum up relpages for tables, indexes
and toast tables), thereby avoiding the overhead of running stat() on
thousands of filesystem tables, but I've come up against what seems to
be an unsuperable
