Java_JDBC一般写法

1.查询

String url = "jdbc:mysql://localhost:3306/test_db";
String userName = "root";
String password = "123";
try(Connection conn = DriverManager.getConnection(url, userName,password)) {
    try(PreparedStatment ps = conn.preparedStatement("SELECT * FROM test_table WHERE name=?")) {
        ps.setObject(1, "rick");
        try (ResultSet rs = ps.excuteQuery()) {
            while (rs.next()) {
                System.out.println(rs.getString("name"));
            }
        }
    }
}

2.新增、更新、删除

String url = "jdbc:mysql://localhost:3306/test_db";
String userName = "root";
String password = "123";
try(Connection conn = DriverManager.getConnection(url, userName,password)) {
    try(PreparedStatment ps = conn.preparedStatement("UPDATE test_table SET age = ? WHERE name=?")) {
        ps.setObject(2, "rick");
        ps.setInt(1, 18);
        int n = ps.excuteQuery(); //成功执行的数据条数
    }
}