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SQL Rolling Average Conversions
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SQL Rolling Average Conversions

MediumSQL · PostgreSQL

Problem

How would you use SQL to calculate a 7-day rolling average of daily conversions?

Assume the daily_conversions table contains one row per calendar date. Treat a NULL conversion count as zero and return all available dates.

Output

  1. One row per calendar date with conversion_date, daily_conversions, and rolling_7_day_avg
  2. Include the current date and up to the six preceding dates in each average
  3. Order by conversion_date ascending

Schema

daily_conversions
ColumnTypeDescription
conversion_datePKDATECalendar date for the daily conversion count
conversionsINTNumber of conversions recorded on the date
Tablesdaily_conversions
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