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SQL Top Stores vs District
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SQL Top Stores vs District

HardSQL · PostgreSQL

Problem

Write a SQL query to identify the top-performing Walgreens Boots Alliance stores by monthly sales and compare each store's sales to its district average. Return the top-ranked store or tied stores for every district and calendar month. Include stores with no sales in a month when calculating district averages.

Output

  1. One row per top-ranked store, district, and month
  2. Columns: month_start, district_name, store_id, store_name, monthly_sales, district_average, and sales_vs_district_avg_pct
  3. Include ties, calculate the percentage difference from the district average, and order by month, district, and store ID

Schema

districts
ColumnTypeDescription
district_idPKINTUnique district identifier
district_nameVARCHAR(100)District name
regionVARCHAR(50)Geographic region containing the district
stores
ColumnTypeDescription
store_idPKINTUnique store identifier
store_nameVARCHAR(120)Walgreens Boots Alliance store name
district_idINTDistrict assigned to the store
store_sales
ColumnTypeDescription
sale_idPKINTUnique sales record identifier
store_idINTStore associated with the sales record
sale_dateDATEDate of the sale
amountNUMERIC(12,2)Sales amount for the record
Tablesdistrictsstoresstore_sales
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