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SQL: Compare Weekly Store Metrics
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SQL: Compare Weekly Store Metrics

MediumSQL · PostgreSQL

Problem

Write a SQL query to compare weekly donation volume, staffing hours, and sales by store at Mississippi Staffing.

Use the provided store, donation, and weekly operations data. Treat donation volume as the number of donations. Include weeks appearing in either donations or operations data, and represent missing numeric measures as zero.

Output

  1. One row per store and week with at least one recorded measure.
  2. Columns: store_id, store_name, week_start, donation_volume, staffing_hours, and sales_amount.
  3. Order by store_id, then week_start ascending.

Schema

stores
ColumnTypeDescription
store_idPKINTUnique store identifier
store_nameVARCHAR(100)Mississippi Staffing store name
cityVARCHAR(100)Store city
donations
ColumnTypeDescription
donation_idPKINTUnique donation identifier
store_idINTStore receiving the donation
donated_atDATEDonation date
donation_amountNUMERIC(10,2)Optional reported donation amount
store_weekly_metrics
ColumnTypeDescription
store_idPKINTStore identifier
week_startPKDATEMonday starting the reporting week
staffing_hoursNUMERIC(8,2)Total staffing hours for the week
sales_amountNUMERIC(12,2)Total sales for the week
Tablesstoresdonationsstore_weekly_metrics
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