emu415-week4

How do you communicate with your database?

• By using HTML
• By using JavaScript
• By using Structured Query Language (SQL)
• By using PHP

Which of the following best describes the goal of data normalization in databases?

• To increase data redundancy for faster access

• To simplify user interface design

• To structure data to minimize redundancy and reduce anomalies

• To convert unstructured data into visual reports

What is a primary key?

• A single unique identifier for a record

• A unique key used as a second key in another table

• To ensure that data is secure

What is a foreign key?

• Checking if a related record exists before allowing it to be entered

• A field in a table that forms a relationship link with a primary key in another table

• To ensure that data is secure and only repeated when required

What is the primary key in this database?

• Emp_Id
• Last Name
• Gender
• Title

Which of the following statements about primary and foreign keys is true?

• A primary key and a foreign key are the same and serve the same purpose in a database.

• A foreign key is a secondary key that helps the primary key uniquely identify each row in its own table.

• Primary keys are used in relational databases and foreign keys are used in NoSQL databases.

• A foreign key of a table can reference the primary key of another table.

What should a primary key contain?

• A lot of different values
• A null value
• An unique value

Why is it a bad practice to use a logical key (like an email address) as the primary key in a database?

• Logical keys are easier for users to remember

• Logical keys improve query performance

• Logical keys are consistent and never change

• Logical keys can change, use more storage, and are slower to process than numeric keys

Can a table have multiple foreign keys?

• Yes, a table can have multiple foreign keys

• No, a table can only have one foreign key

• It depends on the database management system

What is the main advantage of using indexes in a database?

• To simplify database design

• To ensure data integrity

• To speed up data retrieval operations

• To increase the size of the database