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SQL interview question: Employees Hired on the Same Day

Find Employees Hired on Same Day

HR wants to identify orientation cohorts - groups of employees hired on the same date.

Find all hire dates where multiple employees were hired.

Return hire_date and employees_hired (count). Use HAVING COUNT(*) > 1 to filter.

Skills: GROUP BY with HAVING for filtering aggregates

Tables

employees 37 rows
  • id integer PK
  • first_name text
  • last_name text
  • email text
  • department_id integer → departments
  • salary integer
  • hire_date text
  • manager_id integer → employees
  • title text
idfirst_namelast_nameemaildepartment_idsalaryhire_datemanager_idtitle
1AliceChen[email protected]12500002015-01-15NULLCEO
2RobertMartinez[email protected]21800002016-03-20NULLCEO
3SarahJohnson[email protected]11500002017-06-101VP Engineering

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