mysql char对应java

CREATE TABLE users (
    id INT AUTO_INCREMENT PRIMARY KEY,
    name CHAR(50),
    gender CHAR(1)
);

import java.sql.*;

public class MySQLExample {
    public static void main(String[] args) {
        String url = "jdbc:mysql://localhost:3306/mydatabase";
        String user = "username";
        String password = "password";

        try (Connection conn = DriverManager.getConnection(url, user, password)) {
            // 插入数据
            String insertQuery = "INSERT INTO users (name, gender) VALUES (?, ?)";
            try (PreparedStatement pstmt = conn.prepareStatement(insertQuery)) {
                pstmt.setString(1, "John Doe");
                pstmt.setString(2, "M");
                pstmt.executeUpdate();
            }

            // 查询数据
            String selectQuery = "SELECT * FROM users";
            try (Statement stmt = conn.createStatement();
                 ResultSet rs = stmt.executeQuery(selectQuery)) {
                while (rs.next()) {
                    System.out.println("ID: " + rs.getInt("id"));
                    System.out.println("Name: " + rs.getString("name"));
                    System.out.println("Gender: " + rs.getString("gender"));
                }
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}