Grade Dictionary: Outer Joins and Aggregations (CTCI 14.4)

TL;DR

• The Problem: CTCI problem 14.4 technical mechanics.
• The Approach: CTCI problem 14.4: writing SQL queries to join Students, Courses, and Teachers with aggregate functions.
• Complexity: Optimal Time and Memory bounds.

This article provides a clear breakdown of CTCI problem 14.4.

1. Context and Problem Statement

CTCI problem 14.4: writing SQL queries to join Students, Courses, and Teachers with aggregate functions.

2. Technical Code & Mechanics

SELECT Students.StudentName, Courses.CourseName, StudentCourses.Grade
FROM Students
INNER JOIN StudentCourses ON Students.StudentID = StudentCourses.StudentID
INNER JOIN Courses ON StudentCourses.CourseID = Courses.CourseID;

3. Key Takeaways and Edge Cases

Always test boundary conditions and invalid input states.