Every dashboard load ran a SUM and a COUNT over a 1.2-billion-row table, and each one took just over two seconds. At 110,000 monthly active users hammering those dashboards, our Azure SQL sat at 78% CPU and every campaign view felt like wading through mud. The fix wasn't a bigger database tier. It was realizing that you never make a billion-row aggregate fast — you make sure you never run it.
This is the data-architecture story behind one of the numbers we're proudest of on Mattrx, our multi-tenant marketing-analytics SaaS: KPI query p95 from 2,100ms to 48ms, on a CampaignEvents table that holds 1.2 billion rows across ~90 days of daily partitions, under a dashboard read load that peaks near 3,200 requests a second.
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