Comment by qeternity
18 days ago
Does not instill confidence when the queries they provide don't work.
For anyone curious, the corrected query:
SELECT sum(blks_hit)::numeric / nullif(sum(blks_hit + blks_read), 0) AS cache_hit_ratio FROM pg_stat_database;
I just ran their query, and it works
It does not in PG17.
Works on this Postgres 17.7:
postgres=# show server_version; server_version ------------------------------- 17.7 (Debian 17.7-3.pgdg13+1) (1 row)
postgres=# SELECT sum(blks_hit)/nullif(sum(blks_hit+blks_read),0) AS cache_hit_ratio FROM Pg_stat_database; cache_hit_ratio ------------------------ 0.99448341937558994728 (1 row)