Serve the daily players chart from a per-day totals table - #30
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Counting PlayerDay rows per day meant a sequential scan of every monthly partition, so the home page's all-time range took ages. No index could have helped: Postgres has no index-skip-scan for aggregates, so even a covering index still walks every entry. Add a GlobalDay table holding one row per rolled-up day, written inside the rollup transaction and backfilled by the migration, and read it from the chart, the status page, and the backfill worker's rolled-up-day scan, which ran the same unfiltered groupBy on every tick. The API response now carries Cache-Control, so switching back to a range already viewed is served from the browser cache. Chart labels take the year once the range needs it: MMM d, then MMM d, yyyy across a year boundary, then MMM yyyy past a year. They are built from the UTC calendar day, which also fixes every label rendering a day early west of Greenwich. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
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Counting
PlayerDayrows per day meant a sequential scan of every monthly partition, so the home page's all-time range took ages — and no index could have helped, since Postgres has no index-skip-scan for aggregates. This adds aGlobalDaytable holding one row per rolled-up day, written inside the rollup transaction and backfilled by the migration, then reads it from the chart, the status page, and the backfill worker's rolled-up-day scan (which ran the same unfilteredgroupByon every tick). The API response now carriesCache-Control, so switching back to a range already viewed is served from the browser cache. Chart labels take the year once the range needs one —MMM d, thenMMM d, yyyyacross a year boundary, thenMMM yyyypast a year — and are built from the UTC calendar day, which also fixes every label rendering a day early west of Greenwich. Verified against a local replica seeded with 1231 days: every range now serves in 5–8 ms.🤖 Generated with Claude Code