/*
中国移动sql面试题:create table test( id number(10) primary key, type number(10) , t_id number(10), value varchar2(6));insert into test values(100,1,1,'张三');insert into test values(200,2,1,'男');insert into test values(300,3,1,'50');insert into test values(101,1,2,'刘二');insert into test values(201,2,2,'男');insert into test values(301,3,2,'30');insert into test values(102,1,3,'刘三');insert into test values(202,2,3,'女');insert into test values(302,3,3,'10');select * from test;*//*利用一条sql语句将上表的数据显示为如下内容:姓名 性别 年龄----------------------张三 男 50刘二 男 30刘三 女 10*/--使用分组方式select max(decode(type, 1, value)) "姓名", max(decode(type, 2, value)) "性别", max(decode(type, 3, value)) "年龄" from test group by t_id--使用表连接方式select t1.value "姓名",t2.value "性别",t3.value "年龄" from(select value,t_id from test where type = 1) t1 ,(select value,t_id from test where type = 2) t2 ,(select value,t_id from test where type = 3) t3 where t1.t_id = t2.t_id and t1.t_id = t3.t_id