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Top Earners via Table Join
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Top Earners via Table Join

MediumSQL · PostgreSQL

Problem

Motorola Solutions is reviewing compensation data for employees supporting the APX radio product line. Write a PostgreSQL query to find the top three employees by total recorded earnings.

Requirements

  1. Use a LEFT JOIN from employees to employee_earnings so employees without earnings records remain eligible with total earnings of zero.
  2. Aggregate all earning records for each employee and treat NULL earning amounts as zero.
  3. Rank employees by total earnings descending, breaking ties with the lower employee_id.
  4. Return exactly the top three employees, including their rank, employee ID, name, and total earnings.

Schema

employees
ColumnTypeDescription
employee_idPKINTUnique employee identifier
employee_nameVARCHAR(100)Employee's full name
job_titleVARCHAR(100)Employee's role
employee_earnings
ColumnTypeDescription
earning_idPKINTUnique earning record identifier
employee_idINTEmployee receiving the earning
earning_amountDECIMAL(12,2)Recorded earning amount
earning_typeVARCHAR(30)Type of earning record
Tablesemployeesemployee_earnings
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