标签：font pre student 英语 class commit 语文 数学 arch
数据准备阶段：
CREATE TABLE CC (Student NVARCHAR2(2),Course NVARCHAR2(2),Score INT);
INSERT into CC
select N‘张三‘,N‘语文‘,78 from dual union all
select N‘张三‘,N‘数学‘,87 from dual union all
select N‘张三‘,N‘英语‘,82 from dual union all
select N‘张三‘,N‘物理‘,90 from dual union all
select N‘李四‘,N‘语文‘,65 from dual union all
select N‘李四‘,N‘数学‘,77 from dual union all
select N‘李四‘,N‘英语‘,65 from dual union all
select N‘李四‘,N‘物理‘,85 from dual ;
commit;
操作如下：
方法一、
select student, sum(decode(course,‘语文‘,score)) 语文, sum(decode(course,‘数学‘,score)) 数学, sum(decode(course,‘英语‘,score)) 英语, sum(decode(course,‘物理‘,score)) 物理, sum(score) from cc group by student；
方法二、
SELECT KIN.*, KIN.a+KIN.b+KIN.c+KIN.d AS TOTAL FROM (SELECT * FROM CC PIVOT ( MAX(SCORE) FOR COURSE IN (‘语文‘ AS A , ‘数学‘ AS B, ‘英语‘ AS C,‘物理‘ AS D) ) ) KIN;
方法三、
select student， sum(case when course = ‘语文‘ then score else 0 end )语文, sum(case when course = ‘数学‘ then score else 0 end )数学, sum(case when course = ‘英语‘ then score else 0 end )英语, sum(case when course = ‘物理‘ then score else 0 end )物理 from cc group by student;
完。
标签：font pre student 英语 class commit 语文 数学 arch
原文地址：https://www.cnblogs.com/hello-wei/p/10283527.html
