System Design · Senior · Question 73 of 75

A dashboard runs a heavy aggregation on every page load. What is a common fix?

✓Correct answer: Precompute results into a materialized view or summary table, refreshed periodically or incrementally
2Run the query in the browser
3Add more indexes to every column

Explanation

It trades freshness for speed; show "updated N minutes ago" so users know the data lag.

Further reading

Wikipedia: Materialized view ↗

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