一、行转列
1）decode方式
with courses as(
select'001' user_id ,'张三' user_name,'语文' course,67 score from dual unionall
select'001' user_id ,'张三' user_name,'数学' course,76 score from dual unionall
select'001' user_id ,'张三' user_name,'英语' course,100 score from dual unionall
select'002' user_id ,'李四' user_name,'语文' course,70 score from dual unionall
select'002' user_id ,'李四' user_name,'数学' course,90 score from dual unionall
select'002' user_id ,'李四' user_name,'英语' course,120 score from dual
)
SELECT USER_ID,USER_NAME,
SUM(DECODE(course,'语文',score,0)) 语文,--这里使用max,min都可以
SUM(DECODE(course,'数学',score,0)) 数学,
SUM(DECODE(course,'英语',score,0)) 英语
FROM courses
GROUPBY USER_ID ,USER_NAME
执行结果：
| USER_ID | USER_NAME | 语文 | 数学 | 英语 |
| 001 | 张三 | 67 | 76 | 100 |
| 002 | 李四 | 70 | 90 | 120 |
2)CASE WHEN 表达式
with courses as(
select'001' user_id ,'张三' user_name,'语文' course,67 score from dual unionall
select'001' user_id ,'张三' user_name,'数学' course,76 score from dual unionall
select'001' user_id ,'张三' user_name,'英语' course,100 score from dual unionall
select'002' user_id ,'李四' user_name,'语文' course,70 score from dual unionall
select'002' user_id ,'李四' user_name,'数学' course,90 score from dual unionall
select'002' user_id ,'李四' user_name,'英语' course,120 score from dual
)
SELECT USER_ID,USER_NAME,
sum(casewhen course='语文'then score end) "语文",
sum(casewhen course='数学'then score end) "数学",
sum(casewhen course='英语'then score end) "英语"
from courses
groupby USER_ID ,USER_NAME
二、列转行
1）UNION ALL
with courses as(
select'001' user_id ,'张三' user_name,67 ch_score,76 math_score,100 eng_score from dual
union
select'002' user_id ,'李四' user_name,70 ch_score,90 math_score,120 eng_score from dual
)
select user_id,user_name,'语文' course,ch_score score from courses
union
select user_id,user_name,'数学' course,math_score score from courses
union
select user_id,user_name,'英语' course,eng_score score from courses
查询结果：
| USER_ID | USER_NAME | COURSE | SCORE |
| 002 | 李四 | 数学 | 90 |
| 001 | 张三 | 数学 | 76 |
| 002 | 李四 | 英语 | 120 |
| 001 | 张三 | 英语 | 100 |
| 002 | 李四 | 语文 | 70 |
| 001 | 张三 | 语文 | 67 |
2）INSERT ALL
语句如下：
createtable lie2hang_result(
idnumber,
namevarchar2(20),
course varchar2(20),
score number
);
insertall
into lie2hang_result(id,name,course,score) values(id,name,'语文',chinese)
into lie2hang_result(id,name,course,score) values(id,name,'数学',math)
into lie2hang_result(id,name,course,score) values(id,name,'英语',english)
into lie2hang_result(id,name,course,score) values(id,name,'历史',history)
into lie2hang_result(id,name,course,score) values(id,name,'化学',chemistry)
selectid,name,chinese,math,english,history,chemistry from lie2hang;