LeetCode solutions

1942. Primary Department for Each Employee

My accepted SQL solution to LeetCode problem 1942, Primary Department for Each Employee, running in 513ms.

Difficulty: Easy
SQL
Runtime 513ms
Memory 0.0B

By Pranay Mahendrakar
Updated 20 Aug 2026

Read the problem on LeetCode View on GitHub

The problem statement is LeetCode’s and stays on their site. What follows is my accepted solution.

SQL

Accepted on LeetCode — runtime 513ms, memory 0.0B, accepted 2025-12-31.

sql

SELECT employee_id, department_id
FROM Employee
WHERE primary_flag = 'Y'
UNION
SELECT employee_id, department_id
FROM Employee
GROUP BY employee_id
HAVING COUNT(employee_id) = 1

Source