Describe a schema (or classes) to power an online restaurant reservation system. Describe the tables and the relationships beween the tables.

This system should allow a user to reserve a table at a restaurant for a certain time period and a certain party size.

It should allow the restauranteur to configure the system to describe their restaurant and manage reservations.

Think http://opentable.com

What is a database index? When would you use one? What's the downside of using an index?

Complete the following Django model to illustrate how a manufacturer can make many different types of cars.

Give manufacturer a name, founding date and a country.

Give car a name, cost, engine capacity and color. Assume that the manufacturer makes cars in only {red, green, blue and pink}.

class Manufacturer(models.Model):
    # A car manufacturer

class Car(models.Model):
    # A type of car

Assume that you have access to an employee's email Inbox, and that you can parse the content of their emails, including the email headers.

1. How can you use this to deduce their first-degree connections?
2. What kind of heuristics can you come up with to quantify the strength of these first-degree connections?
3. How can you use this to deduce their second-degree connections?
4. How can you use this to deduce their third-degree connections?

1. Describe how you would store a social graph in a relational database.
2. Describe an efficient algorithm to determine whether or not person X is a 2nd degree connection of person Y.
3. Describe an efficient algorithm to determine whether or not person X is a 3rd degree connection of person Y.
4. How can you make #3 very quick. E.g. how does Linked In compute 3rd degree connections quickly?

What's the difference between a primary key and a unique key? What's a foreign key? What's a composite key?

When should you consider denormalizing data? What are the advantages of doing this? What are the disadvantages?

What is an artificial (derived) primary key? When should it be used? How would you compare this to using a natural primary key?

Explain how you would implement the following database relationships when designing tables:

• one to one
• one to many
• many to many

Explain what the following Django model code does? What's the relationship between topping and pizza?

class Topping(models.Model):
    # ...

class Pizza(models.Model):
    # ...
    toppings = models.ManyToManyField(Topping)

Describe a schema (or classes) to power an online car rental system. Describe the tables and the relationships beween the tables.

Model the animal kingdom as a set of classes. Discuss the species, their behavior and properties.

Design the schema or the classes to implement a library for building card games with. This library should make it easy to build games like Rummy, Poker, Hearts, Whist etc.

Outline the implementation for two of the most important methods of the Deck class.