lishenghan 发表于 2018-9-28 06:21:15

Mysql面试题精选

  我有个同学最近在学Mysql数据库,为了测试自己的学习成果,他们老大出了6道Mysql试题让他去做,晚上回来他又分享给我,我感觉非常经典,记录了这几道试题已及答案。
  将测试数据表导入数据库,其中name字段代表“姓名”,score字段代表“分数”。
  create table `t1` (
  `id` double ,
  `name` varchar (300),
  `score` double
  );
  insert into `t1` (`id`, `name`, `score`) values('1','n1','59');
  insert into `t1` (`id`, `name`, `score`) values('2','n2','66');
  insert into `t1` (`id`, `name`, `score`) values('3','n3','78');
  insert into `t1` (`id`, `name`, `score`) values('4','n1','48');
  insert into `t1` (`id`, `name`, `score`) values('5','n3','85');
  insert into `t1` (`id`, `name`, `score`) values('6','n5','51');
  insert into `t1` (`id`, `name`, `score`) values('7','n4','98');
  insert into `t1` (`id`, `name`, `score`) values('8','n5','53');
  insert into `t1` (`id`, `name`, `score`) values('9','n2','67');
  insert into `t1` (`id`, `name`, `score`) values('10','n4','88');
  1. 单分数最高的人和单分数最低的人。
  mysql> select name,max(score) from t1;
  2. 两门分数加起来的第2至5名。
  mysql> select name,sum(score) from t1 group by name order by sum(score) desc limit 1,4;
  +------+------------+
  | name | sum(score) |
  +------+------------+
  | n3   |      163 |
  | n2   |      133 |
  | n1   |      107 |
  | n5   |      104 |
  +------+------------+
  3. 两门总分数在150分以下的人。
  select name sum(score) from t1 group by name having sum(score) < 150;
  4. 两门平均分数介于60和80的人。
  select name,avg(score) from t1 group by name having avg(score) between 60 and 80;
  select name,avg(score) from t1 group by name having ave(score) >60 and avg(score)select name,sum(score),avg(score) from t1 group by name having sum(score)>150 and avg(score) 150 and avg(score) < 90;

页: [1]
查看完整版本: Mysql面试题精选