Practice Join Operations (1.4.1) - Database Management - Full Stack Web Development Advance

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9 questions

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3 cards from this section. Quick, good the night before a test.
Exercise
6 questions · about 4 min · pass mark 70%. Hints available.
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Quiz
3 questions · about 2 min · pass mark 70%. Hints available.
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6 sample questions

Question 1.
What does an INNER JOIN do?
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Think about how it filters records.
Question 2.
Explain what a LEFT JOIN does.
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Remember, unmatched records from the right will show NULLs.
3Question 3.
What type of join returns records with matching values in both tables?
- INNER JOIN
- LEFT JOIN
- RIGHT JOIN
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Focus on matching values.
4Question 4.
True or False: A LEFT JOIN will always return rows even if there are no matches in the right table.
- True
- False
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Consider what happens to unmatched records.
Question 5.
Given two tables: 'students' (id, name) and 'enrollments' (student_id, course_id), write a query using LEFT JOIN to select all students and their enrolled courses. Include students not enrolled in any course.
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Remember to include all students, regardless of their enrollment status.
Question 6.
Using RIGHT JOIN, write a query to find all courses and the students enrolled in them, including courses with no students enrolled.
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Focus on ensuring all courses are listed.

5 more questions in this section. Enroll free to practise them all.