小编dai*_*isy的帖子

假设您有以下表格和数据：

create table t (
    k int,
    v int,
    index k(k)
    ) engine=memory;

insert into t (k, v)
values (10, 1),
       (10, 2),
       (10, 3);

发出select * from t where k = 10noorder by子句时，MySQL默认如何对记录进行排序？

这是我的数据库方案的最小案例：

CREATE TABLE `test` (
  `id` int(11) NOT NULL,
  `name` varchar(22) DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `id` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

 CREATE TABLE `test2` (
  `id` int(11) NOT NULL,
  PRIMARY KEY (`id`),
  CONSTRAINT `test2_ibfk_1` FOREIGN KEY (`id`) REFERENCES `test` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8

好吧，还有我们里面的东西：

    mysql> select * from test;
+-----+-------+
| id  | name  |
+-----+-------+
| 111 | AAABA |
+-----+-------+
1 row in set (0.00 sec)

mysql> select * from test2;
+-----+
| id …