SQL sloution
Code\n\nSELECT employee_id FROM Employees WHERE employee_id not in (SELECT employee_id FROM Salaries)\n  UNION\nSELECT employee_id FROM Salaries\n   WHERE emplo
# Code\n```\nSELECT employee_id FROM Employees WHERE employee_id not in (SELECT employee_id FROM Salaries)\n  UNION\nSELECT employee_id FROM Salaries\n   WHERE employee_id NOT IN (SELECT employee_id FROM Employees)\nORDER BY employee_id\n```
['Oracle']