Part 3/8:
- Imputing missing values using mean, median, or categorical filling techniques.
SQL Proficiency: Finding Salaries and Joins
Interviewers frequently assess SQL skills. Questions may involve writing queries for specific scenarios.
- Find the Second Highest Salary: Candidates must demonstrate knowledge of SQL conventions, such as using subqueries.
SELECT MAX(salary) AS SecondHighestSalary
FROM Employees
WHERE salary < (SELECT MAX(salary) FROM Employees);
- Inner Join vs. Left Join: Candidates should explain that an inner join returns matching rows from both tables, while a left join includes all rows from the left table and nulls for unmatched rows from the right.