I have been testing queries with the same data in PostgreSQL 9.6.11 and PostgreSQL 12.3 using the TABLESAMPLE bernoulli
clause. It seems PostgreSQL 12.3 executes the query about 25x faster than the old version. Before i dig into other performance optimizations, i tried looking into the documentation for the two versions for clues about performance improvements between v9.6 and v12.3. I didn't see any.
Does anyone know if there have been performance improvements to TABLESAMPLE
in recent PostgreSQL versions?