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Data Analysis and Revenue Leakage
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Data Analysis and Revenue Leakage

MediumSQL · PostgreSQL

Problem

What is your experience with analyzing data, recognizing revenue leakages, and which Excel tools do you use?

For this SQL exercise, use the bookings and charges tables to identify booking-level revenue leakage. Include confirmed or completed bookings where expected revenue exceeds settled charges.

Output

  1. One row per booking with leakage.
  2. Columns: booking_id, sailing_date, expected_revenue, collected_revenue, revenue_leakage, and leakage_reason.
  3. Sort by revenue_leakage descending, then booking_id ascending.

Schema

bookings
ColumnTypeDescription
booking_idPKINTUnique booking identifier
sailing_dateDATEScheduled sailing date
expected_revenueNUMERIC(12,2)Revenue expected from the booking
booking_statusVARCHAR(20)Current booking status
source_systemVARCHAR(30)System that originated the booking
charges
ColumnTypeDescription
charge_idPKINTUnique charge identifier
booking_idINTBooking associated with the charge
amountNUMERIC(12,2)Charge amount
charge_statusVARCHAR(20)Processing status of the charge
charge_typeVARCHAR(20)Type of booking charge
Tablesbookingscharges
Interviewer

Your question is Data Analysis and Revenue Leakage. Start with the requirements and the two tables in the Question tab.

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