(Hard to draw many meaningful conclusions from a single, extremely simple query without much explanation?)

Graph shows PostgreSQL as taking a long time, but doesn't say anything about configuration or parallelization. PostgreSQL should be able to parallelize that type of query since 9.6+, but I think they didn't use parallelization in these experiments with PostgreSQL, even though they used a bunch of parallel threads with QuestDB?

So would be good to know:

- What version of Postgres

- How many parallel workers for this query

- If employing JIT'ing the query

- If pre-warming the cache in PostgreSQL and configuring it to store fully in memory (as benchmarks with QuestDB appeared to do a two-pass to first mmap into memory, and only accounting for the second pass over in-memory data).

etc

Database benchmarking is pretty complex (and easy to bias), and most queries do not look like this toy one.