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Rolling 7-Day System Error Average

Hard

Window FunctionsDate FunctionsRunning Totals

Problem

Task

You are given daily system error logs and asked to calculate a rolling 7-day average of errors for each day in the series. Use PostgreSQL-compatible SQL to return one row per calendar day with the daily error count and the 7-day trailing average, including days with zero errors. Do not use MySQL-only syntax.

Problem

Task

You are given daily system error logs and asked to calculate a rolling 7-day average of errors for each day in the series. Use PostgreSQL-compatible SQL to return one row per calendar day with the daily error count and the 7-day trailing average, including days with zero errors. Do not use MySQL-only syntax.

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PostgreSQL

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Rolling 7-Day System Error Average | Dataford Interview Questions