[qeternity]

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;

[itiswatitis]

I just ran their query, and it works

[qeternity]

It does not in PG17.