如何查询MySQL中某个表的索引信息

SHOW INDEX FROM table_name;

SELECT TABLE_NAME, INDEX_NAME, COLUMN_NAME, NON_UNIQUE, INDEX_TYPE
FROM information_schema.statistics
WHERE table_schema = 'your_database_name'
  AND table_name = 'your_table_name';

DESCRIBE table_name;

DESC table_name;

import java.sql.*;

public class OrderQuery {
    public static void main(String[] args) {
        try {
            // 连接数据库
            Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mydatabase", "username", "password");

            // 创建索引
            Statement stmt = conn.createStatement();
            stmt.execute("CREATE INDEX idx_user_id ON `order` (UserID)");

            // 查询订单信息
            PreparedStatement pstmt = conn.prepareStatement("SELECT * FROM `order` WHERE UserId = ?");
            pstmt.setInt(1, 1);
            ResultSet rs = pstmt.executeQuery();

            // 打印查询结果
            while (rs.next()) {
                int orderId = rs.getInt("ID");
                int userId = rs.getInt("UserID");
                String product = rs.getString("Product");
                int quantity = rs.getInt("Quantity");
                double price = rs.getDouble("Price");
                System.out.println("Order ID: " + orderId + ", User ID: " + userId + ", Product: " + product +
                        ", Quantity: " + quantity + ", Price: " + price);
            }

            // 关闭数据库连接
            rs.close();
            stmt.close();
            pstmt.close();
            conn.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}