mysql 데이터베이스에서 데이터를 가져오는 방법

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

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

<code class="python">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()</code>

<code class="java">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();
    }
}</code>