Question: Subquery in the SELECT Clause
Explore how to use subqueries within the SELECT clause to combine data from Employees, Skills, and Projects tables. Understand how to write queries that reveal which employee is working on which project, improving your SQL querying skills for interviews.
We'll cover the following...
Question
Given the following Employees, Skills, and Projects table structures:
Employees
EmpID | EmpName | Salary |
1 | Susan Lee | 50000.00 |
2 | Alexa Smith | 60000.00 |
3 | Sana Amberson | 45000.00 |
4 | Sarah Ronald | 47000.00 |
Skills
SkillID | EmpID | SkillName |
1 | 1 | C++ |
2 | 4 | Java |
3 | 1 | Python |
4 | 3 | Blender |
5 | NULL | Android |
Projects
ProjectID | EmpID | SkillID | ProjectName |
1 | 1 | 1 | Industrial Robot |
2 | 4 | 2 | Multiplatform GUI |
3 | 3 | 4 | 3D Simulation |
4 | 1 | 3 | Deep Learning Model |
5 | NULL | NULL | IOS App |
6 | 1 | NULL | Advanced Calculator |
7 | NULL | 5 | Android App |
Additional information
The Employees table consists of the following columns:
EmpID: Unique identifier for each employee ...