How to get data from mysql database

We can obtain MySQL data through the following methods: Use the MySQL command line client to connect to the database and use the SELECT statement to retrieve the data. Connect and query using Python's MySQL Connector/Python library. Connect and execute queries using Java's JDBC.

How to obtain the data in the MySQL database

There are many ways to obtain the data in the MySQL database, as follows Are some of the most commonly used methods:

1. Use the MySQL command line client

• Open the MySQL command line client.
• Connect to the database using the following syntax:

<code>mysql -u username -p password -D database_name</code>

• where username is your MySQL username and password is you password, database_name is the name of the database you want to connect to.
• Enter the password and press Enter.
• Use SELECT statement to retrieve data:

<code>SELECT column_name(s)
FROM table_name
WHERE condition;</code>

2. Use Python

##Use
• MySQL Connector/Python Library:

import mysql.connector

# 建立数据库连接
connection = mysql.connector.connect(
    host="localhost",
    user="username",
    password="password",
    database="database_name"
)

# 获取游标
cursor = connection.cursor()

# 执行查询
cursor.execute("SELECT * FROM table_name")

# 获取查询结果
results = cursor.fetchall()

# 遍历结果
for row in results:
    print(row)

# 关闭游标和连接
cursor.close()
connection.close()

3. Using Java

Using
• Java Database Connectivity (JDBC)：

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class GetMySQLData {

    public static void main(String[] args) {
        // 建立数据库连接
        Connection connection = DriverManager.getConnection(
                "jdbc:mysql://localhost/database_name", "username", "password");

        // 创建声明
        Statement statement = connection.createStatement();

        // 执行查询
        ResultSet resultSet = statement.executeQuery("SELECT * FROM table_name");

        // 遍历结果
        while (resultSet.next()) {
            System.out.println(resultSet.getString("column_name"));
        }

        // 关闭声明和连接
        statement.close();
        connection.close();
    }
}

The above is the detailed content of How to get data from mysql database. For more information, please follow other related articles on the PHP Chinese website!