Dataford
Interview QuestionsInterview GuidesExperiencesMock InterviewsPricing
Get started
Rolling 7-Day Prescriptions Average
00:00
5 left

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
Interviewer

Your question is Rolling 7-Day Prescriptions Average. Start with the requirements and the one table in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

You need to log in / sign up to run or submit.
CodePostgreSQL
You need to log in / sign up to run or submit.Ln 1
Run your query to see results here.