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Find Multi-Unit Customers
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Find Multi-Unit Customers

MediumSQL · PostgreSQL

Problem

Write a SQL query to identify customers who have rented multiple storage units across different locations within the same month at Extra Space Storage.

Use the customers, rentals, and storage_units tables. Treat distinct storage units and distinct locations separately when determining eligibility.

Output

  1. One row per qualifying customer and rental month.
  2. Columns: customer_id, customer_name, rental_month, unit_count, location_count, and locations.
  3. Include only customers with more than one distinct unit and more than one distinct location in the same month.
  4. Order by customer_id, then rental_month.

Schema

customers
ColumnTypeDescription
customer_idPKINTUnique customer identifier
customer_nameVARCHAR(100)Customer's full name
storage_units
ColumnTypeDescription
unit_idPKINTUnique storage unit identifier
location_nameVARCHAR(100)Extra Space Storage facility location
rentals
ColumnTypeDescription
rental_idPKINTUnique rental record identifier
customer_idINTCustomer who rented the unit
unit_idINTStorage unit rented
rented_atDATEDate the rental began
Tablescustomersrentalsstorage_units
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