MySQL table design tutorial: Create a simple question and answer table

MySQL table design tutorial: Create a simple question and answer table

Introduction:
In the database system, table design is a very important part. Good table design can improve the efficiency and performance of the database, making data storage and query more convenient and effective. This article will take creating a simple question and answer table as an example, introduce the table design and creation process in MySQL, and provide code examples.

1. Requirements Analysis
Before starting to design the table, we need to clarify the requirements. Suppose we need to create a question and answer table to store questions and corresponding answers.

The requirements are as follows:

1. Each question has a unique ID and question content.
2. Each question can have multiple answers, and each answer has a unique ID and answer content.

Based on the above requirements, we can design the following table structure.

2. Table design
According to requirements, we can design the following table structure.

Questions:

ID	question_content
1	How to design a database table?
2	What is the difference between primary key and foreign key?

Answers:

##3Another answer for question 1.1## 3. Create a table

ID	answer_content	question_id
1	To design a database table, you need to consider the data types, constraints, and relationships between tables.	1
2	Primary key is used to uniquely identify a record in a table, while foreign key is used to establish a relationship between two tables.	2

In MySQL, you can use DDL (Data Definition Language) statements to create tables. Below is sample code to create a question table and answer table.

Create question table:

1. CREATE TABLE questions (
     ID INT NOT NULL AUTO_INCREMENT,
     question_content VARCHAR(255) NOT NULL,
     PRIMARY KEY (ID)
   );

Create answer table:

2. CREATE TABLE answers (
     ID INT NOT NULL AUTO_INCREMENT,
     answer_content VARCHAR(255) NOT NULL,
     question_id INT NOT NULL,
     PRIMARY KEY (ID),
     FOREIGN KEY (question_id) REFERENCES questions(ID)
   );

In the above example, we used INT and VARCHAR data type to define columns. The ID column uses the AUTO_INCREMENT attribute to ensure that each question and answer has a unique ID. The question_id column is used in the answers table to establish a foreign key relationship with the question table.

4. Insert data

After the table is created, we can insert data to test the correctness and integrity of the table. The following is sample code to insert data into the question table and answer table.

Insert data into the question table:

1. INSERT INTO questions (question_content) VALUES
     ('How to design a database table?'),
     ('What is the difference between primary key and foreign key?');

Insert data into the answer table:

2. INSERT INTO answers (answer_content, question_id) VALUES
   ('To design a database table, you need to consider the data types, constraints, and relationships between tables.', 1),
   ('Primary key is used to uniquely identify a record in a table, while foreign key is used to establish a relationship between two tables.', 2),
   ('Another answer for question 1.', 1);

5. Summary

This article introduces the basic process of MySQL table design, taking the creation of a simple question and answer table as an example, and provides code examples for the design and creation of question tables and answer tables respectively. These examples can help readers understand the design principles and practical operation of tables. In the actual database design and development, table design is carried out according to specific needs, and optimization and adjustment are made according to the actual situation to improve the efficiency and performance of the database.

Reference materials:

MySQL Documentation: https://dev.mysql.com/doc/

1. Quick Guide to Database Design: https://www .vertabelo.com/blog/technical-articles/a-quick-guide-to-database-design

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