2.向TEST表中添加数据
INSERT INTO TEST(STUDENT,COURSE,SCORE) select '张三','语文',78 from dual union select '张三','数学',87 from dual union select '张三','英语',82 from dual union select '张三','物理',90 from dual union select '李四','语文',65 from dual union select '李四','数学',77 from dual union select '李四','英语',65 from dual union select '李四','物理',85 from dual
表数据如下:
3.列转行
方法··1:
select Student, sum(decode(Course, '数学', Score)) 数学, sum(decode(Course, '物理', Score)) 物理, sum(decode(Course, '英语', Score)) 英语, sum(decode(Course, '语文', Score)) 语文 from TEST group by Student
注意:如果在decode()方法中加入第4个参数。如decode(Course, '数学', Score, -1)则外层使用sum可能会出问题,推荐使用max替换sum。
方法··2:
select Student, sum(case Course when '数学' then Score else null end) 数学, sum(case Course when '物理' then Score else null end) 物理, sum(case Course when '英语' then Score else null end) 英语, sum(case Course when '语文' then Score else null end) 语文 from TEST group by Student
效果如下:
注:sum是求和的意思;比如说里面记录里面有两条张三,列转行显示的结果就会是两个张三的结果之和。
转载自: http://www.cnblogs.com/Mr_JinRui/archive/2011/05/27/2060109.html