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Compare Profitability Across Segments
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Compare Profitability Across Segments

HardSQL · PostgreSQL

Problem

You are given transaction-level financial data and need to compare profitability across products, regions, and customer cohorts. Write a PostgreSQL query that returns the monthly gross profit, gross margin, and rank for each segment type, so you can identify the most profitable segments over time.

Schema

transactions
ColumnTypeDescription
transaction_idPKBIGINTUnique transaction identifier
transaction_dateDATEDate the transaction occurred
customer_idBIGINTCustomer who made the transaction
product_idINTProduct sold
region_idINTRegion where the transaction was booked
revenue_amountNUMERIC(12,2)Revenue recognized for the transaction
cost_amountNUMERIC(12,2)Direct cost for the transaction
statusVARCHAR(20)Transaction status
products
ColumnTypeDescription
product_idPKINTProduct identifier
product_nameVARCHAR(100)Product name
product_categoryVARCHAR(50)Product category
regions
ColumnTypeDescription
region_idPKINTRegion identifier
region_nameVARCHAR(50)Region name
customers
ColumnTypeDescription
customer_idPKBIGINTCustomer identifier
customer_nameVARCHAR(100)Customer name
signup_dateDATECustomer signup date
Tablestransactionsproductsregionscustomers
Interviewer

Your question is Compare Profitability Across Segments. Start with the requirements and the four tables in the Question tab.

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