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Rolling 7-Day Prescriptions Average
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Rolling 7-Day Prescriptions Average

MediumSQL · PostgreSQL

Problem

What SQL query would you use to calculate a rolling 7-day average of daily prescriptions by region using window functions?

Use the prescriptions table. Treat each region and calendar date as one daily total. The rolling average should include the current date and prior six calendar days where daily data exists.

Output

  1. One row per region and prescription date.
  2. Columns: region, prescription_date, daily_prescriptions, and rolling_7_day_avg.
  3. Order by region, then prescription_date ascending.

Schema

prescriptions
ColumnTypeDescription
prescription_idPKINTUnique prescription record identifier
regionVARCHAR(50)Geographic region associated with the prescription
prescription_dateDATEDate on which the prescription was recorded
prescription_countINTNumber of prescriptions in the record
Tablesprescriptions
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