数据库期末试题 英文

在大学学习计算机科学的过程中，数据库课程无疑是非常重要的一门课程。作为计算机领域的核心内容之一，数据库的理论和实践都占据着非常重要的位置。期末试题是考察学生对数据库知识的掌握程度和应用能力的重要手段。本篇博文将为大家提供一些关于数据库期末试题的英文示例，帮助大家更好地准备考试。

Part 1: Multiple Choice

1. Which of the following is NOT a relational database management system (RDBMS)?

• a) MySQL
• b) Oracle
• c) MongoDB
• d) PostgreSQL

2. What is the purpose of a primary key in a database table?

• a) It ensures data integrity and uniqueness of records.
• b) It allows for faster retrieval of data.
• c) It provides a way to define relationships between tables.
• d) It is used to create backup copies of the database.

3. Which SQL keyword is used to retrieve data from a database?

• a) SELECT
• b) UPDATE
• c) DELETE
• d) INSERT

4. What is normalization in the context of database design?

• a) It refers to the process of organizing data into tables and columns.
• b) It ensures that each column contains only atomic values.
• c) It eliminates redundant data and minimizes data anomalies.
• d) It allows for efficient storage and retrieval of data.

Part 2: Query Writing

1. Write an SQL query to retrieve all students from the "students" table who have scored more than 90 in the "math" subject.

2. Write an SQL query to calculate the average salary of employees in each department from the "employees" table.

SELECT department, AVG(salary) FROM employees GROUP BY department;

3. Write an SQL query to retrieve the top 5 products with the highest sales from the "products" table.

SELECT * FROM products ORDER BY sales DESC LIMIT 5;

Part 3: Database Design

1. Design a database schema for a library management system. The system should store information about books, borrowers, and loans. Provide the table structures and their relationships.

CREATE TABLE books (
  book_id INT PRIMARY KEY,
  title VARCHAR(100),
  author VARCHAR(50),
  published_year INT,
  available_copies INT
);

CREATE TABLE borrowers (
  borrower_id INT PRIMARY KEY,
  name VARCHAR(50),
  address VARCHAR(100),
  phone_number VARCHAR(20),
  email VARCHAR(100)
);

CREATE TABLE loans (
  loan_id INT PRIMARY KEY,
  book_id INT,
  borrower_id INT,
  loan_date DATE,
  due_date DATE,
  FOREIGN KEY (book_id) REFERENCES books (book_id),
  FOREIGN KEY (borrower_id) REFERENCES borrowers (borrower_id)
);

2. Explain the concept of database normalization and its importance in database design.

Database normalization is the process of organizing data in a database to eliminate redundancy and minimize data anomalies. It involves breaking down a database into multiple tables and defining relationships between them. The main goals of normalization are to ensure data integrity, reduce data duplication, and improve query performance. By following normalization principles, a database can achieve a higher level of efficiency and maintainability.

Part 4: Essay Question

Explain the advantages and disadvantages of using a relational database management system (RDBMS) compared to other types of databases.

Relational database management systems (RDBMS) have several advantages:

• - They provide a structured and organized way to store and retrieve data.
• - They support relationships between tables through primary and foreign keys.
• - They ensure data integrity by enforcing constraints.
• - They have a strong and widely adopted standard language, SQL, for data manipulation.

However, RDBMS also have some disadvantages:

• - They can be complex to design and maintain, especially for large-scale databases.
• - They may have limitations in handling unstructured or semi-structured data.
• - They can be less suitable for certain types of applications, such as real-time or highly scalable systems.
• - They can have performance issues when dealing with complex queries involving multiple tables.

总结起来，数据库期末试题对于学生来说是一个重要的考核方式，通过解答这些试题，学生可以巩固并提升自己的数据库知识和应用能力。希望本篇英文示例能够对大家准备数据库期末考试有所帮助。