{"slug":"trading-api-vs-market-data-api","qid":"quote_firehose","label":"AAPL top of book message volume by ET hour, 16 September 2026","post_title":"Trading API vs Market Data API: Key Differences","post_url":"/blog/trading-api-vs-market-data-api#q-quote_firehose","columns":["et_hour","quote_count","distinct_quote_count","updates_per_second"],"rows":[{"et_hour":"09:00","quote_count":104377,"distinct_quote_count":5955,"updates_per_second":29},{"et_hour":"10:00","quote_count":80296,"distinct_quote_count":1546,"updates_per_second":22.3},{"et_hour":"11:00","quote_count":69167,"distinct_quote_count":1337,"updates_per_second":19.2},{"et_hour":"12:00","quote_count":43725,"distinct_quote_count":794,"updates_per_second":12.1},{"et_hour":"13:00","quote_count":43605,"distinct_quote_count":627,"updates_per_second":12.1},{"et_hour":"14:00","quote_count":122503,"distinct_quote_count":2377,"updates_per_second":34},{"et_hour":"15:00","quote_count":164419,"distinct_quote_count":1735,"updates_per_second":45.7},{"et_hour":"16:00","quote_count":936,"distinct_quote_count":240,"updates_per_second":0.3}],"shape":"ranking","sql":"SELECT\n    formatDateTime(\n        toStartOfHour(toTimeZone(sip_timestamp, 'America/New_York')),\n        '%H:%i')                    AS et_hour,\n    count()                         AS quote_count,\n    uniqExact(bid_price, ask_price) AS distinct_quote_count,\n    round(count() / 3600, 1)        AS updates_per_second\nFROM global_markets.cache_stocks_quotes\nWHERE ticker = 'AAPL'\n  AND sip_timestamp >= '2026-09-16 13:00:00'\n  AND sip_timestamp <  '2026-09-16 21:00:00'\nGROUP BY et_hour\nORDER BY et_hour","computed_at":"2026-10-05T15:10:08.987034+00:00","elapsed":0.002159939}