Many-to-Many Relationships and Python :Using Databases with Python (Python for Everybody Specialization) Answers 2025

Question 1

How do we model a many-to-many relationship between two database tables?

✅ We add a table with two foreign keys
❌ ARRAY column type
❌ 10 foreign keys
❌ BLOB columns

Explanation:
A junction (association) table is used to model many-to-many relationships.
For example, a StudentCourse table connects Students and Courses using two foreign keys: student_id and course_id.

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Question 2

In Python, what is a database “cursor” most like?

✅ A file handle
❌ A method
❌ A function
❌ A dictionary

Explanation:
A cursor acts like a file handle that lets you send SQL commands and fetch rows — similar to reading lines from a file.

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Question 3

What method do you call in an SQLite cursor object in Python to run an SQL command?

✅ execute()
❌ send()
❌ run()
❌ socket()

Explanation:
The execute() method runs a single SQL statement (like SELECT, INSERT, UPDATE, etc.) through the cursor.

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Question 4

In the following SQL:

what is the purpose of the “?”?

✅ It is a placeholder for the contents of the “org” variable
❌ Search wildcard
❌ Multiple boolean operator
❌ Syntax error

Explanation:
In SQLite (and most databases), ? is used as a parameter placeholder to safely insert variables into SQL (avoiding SQL injection).

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Question 5

In the following Python code:

what is the value in row if no rows match the WHERE clause?

✅ None
❌ -1
❌ Empty list
❌ Empty dictionary