MySQL nice and crisp solution
\nSELECT employee_id \nFROM employees\nWHERE employee_id NOT IN (SELECT employee_id FROM salaries)\nUNION\nSELECT employee_id \nFROM salaries\nWHERE employee_id
```\nSELECT employee_id \nFROM employees\nWHERE employee_id NOT IN (SELECT employee_id FROM salaries)\nUNION\nSELECT employee_id \nFROM salaries\nWHERE employee_id NOT IN (SELECT employee_id FROM employees)\nORDER BY employee_id;\n```\nUpvote if you like.
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