bucket-local-time-in-code-not-in-sql

Group events by local hour or local day in application code from one raw scan, not in SQL — the engine's local-time modifier answers from the process time zone rather than the user's, and four local-time aggregates mean four scans that can disagree with each other. Covers where the line sits between an aggregate that belongs in SQL and one that does not, and what the single scan has to return to stay correct. Use…