Django Quiz - 4

1. What does ORM stand for in Django?
a) Object-Related Mapping
b) Object-Relational Mapping
c) Object-Resource Mapping
d) Object-Representation Mapping
Answer: b) Object-Relational Mapping

2. Which of the following is true about Django ORM?
a) It provides a bridge between the database and the application models.
b) It allows you to interact with the database using Python code.
c) It provides a high-level, intuitive API for querying and manipulating data.
d) All of the above.
Answer: d) All of the above.

3. How can you create a new record in the database using Django ORM?
a) By calling the create() method on the model class.
b) By instantiating a new object of the model class and calling the save() method.
c) By executing raw SQL queries with the execute() method.
d) By using the add() method of a related manager.
Answer: b) By instantiating a new object of the model class and calling the save() method.

4. How can you retrieve a single record from the database using Django ORM?
a) By using the get() method on the model class.
b) By executing a raw SQL query with the raw() method.
c) By using the filter() method on the model class.
d) By calling the find() method on the model class.
Answer: a) By using the get() method on the model class.

5. How can you filter records based on specific conditions using Django ORM?
a) By using the filter() method with keyword arguments.
b) By using the exclude() method with keyword arguments.
c) By using the Q() object to create complex queries.
d) All of the above.
Answer: d) All of the above.

6. What does the annotate() method do in Django ORM?
a) It allows you to add calculated fields to query results.
b) It enables you to perform aggregation functions like counting or summing.
c) It provides an interface for ordering query results.
d) It is not a valid method in Django ORM.
Answer: a) It allows you to add calculated fields to query results.

7. How can you perform an inner join between two related models using Django ORM?
a) By using the join() method on the model class.
b) By using the select_related() method on the query set.
c) By using the prefetch_related() method on the query set.
d) By executing a raw SQL query with the raw() method.
Answer: b) By using the select_related() method on the query set.

8. How can you perform a left outer join between two related models using Django ORM?
a) By using the join() method on the model class.
b) By using the select_related() method on the query set.
c) By using the prefetch_related() method on the query set.
d) By executing a raw SQL query with the raw() method.
Answer: c) By using the prefetch_related() method on the query set.

9. How can you order query results based on a specific field in Django ORM?
a) By using the order_by() method on the query set.
b) By using the sort_by() method on the query set.
c) By executing a raw SQL query with the raw() method.
d) By calling the order() method on the model class.
Answer: a) By using the order_by() method on the query set.

10. How can you delete records from the database using Django ORM?
a) By calling the delete() method on a query set.
b) By executing a raw SQL query with the raw() method.
c) By using the remove() method on a related manager.
d) By calling the destroy() method on the model class.
Answer: a) By calling the delete() method on a query set.

11. What is the purpose of using transactions in Django ORM?
a) Transactions ensure that a group of database operations either succeed or fail together.
b) Transactions improve the performance of database queries in Django ORM.
c) Transactions allow for concurrent access and modification of database records.
d) Transactions are not supported in Django ORM.
Answer: a) Transactions ensure that a group of database operations either succeed or fail together.

12. How can you perform raw SQL queries in Django ORM?
a) By using the execute_sql() method on a model's manager.
b) By using the query() method on the model class.
c) By executing a raw SQL query with the raw() method.
d) By calling the sql() method on a query set.
Answer: c) By executing a raw SQL query with the raw() method.