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Top Customers by Last-Quarter Spend

MediumSQL · PostgreSQL00:00
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Your question is Top Customers by Last-Quarter Spend. Start with the requirements and the two tables on the right.

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Problem

Write a PostgreSQL query to find the top three customers by total spend in the last completed quarter by joining customers and transactions. Return customer_id, customer_name, and total_spend, ordered by highest spend first. Assume CURRENT_DATE = '2024-08-15', so the target quarter is 2024-04-01 to 2024-06-30.

Schema

ColumnTypeDescription
customer_id INT PK
customer_name VARCHAR(100)
segment VARCHAR(50)
onboarded_at DATE
ColumnTypeDescription
transaction_id INT PK
customer_id INT FK
transaction_date DATE
amount DECIMAL(10,2)
cost_center VARCHAR(50)

Representative Rows

customers
101Acme HealthEnterprise2023-11-10
102BluePeak RetailMid-Market2024-01-05
104Delta ManufacturingEnterprise2023-09-15
transactions
10021012024-04-01300.00SaaS
10061022024-05-181200.00SaaS
10101042024-06-251600.00Labor
Tablescustomerstransactions
Your solutionPostgreSQL
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