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Rolling 7-Day Average by Region

MediumSQL · PostgreSQL00:00
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Your question is Rolling 7-Day Average by Region. Start with the requirements and the two tables on the right.

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Problem

Write a SQL query to calculate the rolling 7-day average of product sales across different regions.

Use the product and sales data provided. Treat dates with no sales as zero sales, and calculate the average for each product and region over the current date and six preceding calendar dates.

Output

  1. One row per product, region, and calendar date in the sales date range.
  2. Columns: product_name, region, sales_date, daily_sales, and rolling_7_day_avg.
  3. Include dates with no sales and return results ordered by product_name, region, and sales_date ascending.

Schema

products
ColumnTypeDescription
product_idPKINTUnique product identifier
product_nameVARCHAR(150)Product name
product_categoryVARCHAR(100)Product category
sales
ColumnTypeDescription
sale_idPKINTUnique sales transaction identifier
product_idINTProduct sold
regionVARCHAR(80)Sales region
sale_dateDATEDate of the sale
quantityINTUnits sold
Tablesproductssales
Your solutionPostgreSQL
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