A query builder writes the same typed-value expression (an inlinable SQL function such as value_of(r.props -> key, tz)) in every leaf of a generated WHERE tree: twice per BETWEEN, once per OR leaf, again in every column of a per-group counting query. Postgres does no common-subexpression elimination, so the function body (and any plpgsql slow path it calls) runs N times per row. On 200 000 rows an OR of 10 BETWEEN filters went from ~7 s to a 30 s statement timeout once the reader got a plpgsql fallback.