On 2020-Nov-10, Kyotaro Horiguchi wrote: > In second thought about the reason for the "toprel_oid". It is perhaps > to avoid "wrongly" propagated values to ancestors after a manual > ANALYZE on a partitioned table. But the same happens after an > autoanalyze iteration if some of the ancestors of a leaf relation are > analyzed before the leaf relation in a autoanalyze iteration. That > can trigger an unnecessary analyzing for some of the ancestors.
I'm not sure I understand this point. I think we should only trigger this on analyzes of *leaf* partitions, not intermediate partitioned relations. That way you would never get these unnecesary analyzes. Am I missing something? (So with my proposal in the previous email, we would send the list of ancestor relations after analyzing a leaf partition. Whenever we analyze a non-leaf, then the list of ancestors is sent as an empty list.) > > > Regarding the counters in pg_stat_all_tables: maybe some of these should > > > be > > > null rather than zero ? Or else you should make an 0001 patch to fully > > > implement this view, with all relevant counters, not just > > > n_mod_since_analyze, > > > last_*analyze, and *analyze_count. These are specifically misleading: > > > > > > last_vacuum | > > > last_autovacuum | > > > n_ins_since_vacuum | 0 > > > vacuum_count | 0 > > > autovacuum_count | 0 > > > > > I haven't modified this part yet, but you meant that we should set > > null to counters > > about vacuum because partitioned tables are not vacuumed? > > Perhaps bacause partitioned tables *cannot* be vacuumed. I'm not sure > what is the best way here. Showing null seems reasonable but I'm not > sure that doesn't break anything. I agree that showing NULLs for the vacuum columns is better. Perhaps the most reasonable way to do this is use -1 as an indicator that NULL ought to be returned from pg_stat_get_vacuum_count() et al, and add a boolean in PgStat_TableCounts next to t_truncated, maybe "t_nullvacuum" that says to store -1 instead of 0 in pgstat_recv_tabstat.
