"fair" means that we comparing apples to apples. Ad-hoc, unindexed predicate, compiled by QuestDB into AVX2 assembly (using AsmJIT) vs same predicate complied by Clickhouse (I'm assuming by LLVM). One can perhaps view this as comparing SIMD-based scans from both databases. Perhaps we generate better assembly, which incidentally offers better IO.

We all understand that creating very specific index might improve specific query performance. Great, Clickhouse geared the entire table storage model to be ultra specific for latitude search. What if you search by longitude, or other column? Back to the beginning.

JIT-compiled predicates offer arbitrary query optimisation with zero impact on ingestion. This is sometimes useful.

What would you offer assuming that we reached out, other than creating an index?

Clickhouse does better than we do in other areas. It JITs more complicated expressions, such as some date functions. It optimises count() queries specifically. For example we collect "found" rowed_ids in an array. Clickhouse does not specifically for count(). We still have work to do. On other hand we ingested this very dataset about 5x quicker than clickhouse, which we left out because article is not about "QuestDB is faster than Clickhouse"

The million dollar question is, if we add the same index optimization to QuestDB, would QuestDB query faster than Clickhouse?

What if the purpose of the article is to compare queries without indexes?

So, maybe do not create specific scenarios for corner cases and then generalize outcome? And write articles about common scenarios that is important for people who will use technology on daily basis.

My personal view is that having fast queries without indexes is quite general outcome.