列转行实验：
create table score2(
name varchar2(10),
Language number(3),
Math number(3),
English number(3)
);
insert into
score2 values('Zhang',80,67,95);
insert into score2 values('Li',79,84,62);
insert into score2(name,Language) values('Chen',88);
commit;
SELECT name,
'Language' subject,Language grade FROM score2
UNION ALL
SELECT name, 'Math' subject,Math grade FROM score2
UNION ALL
SELECT name, 'English' subject,English grade FROM score2
order by name;
多列转成一行 实验：
drop table t purge;
create table t(
dname varchar2(10),
ename varchar2(10)
);
insert into t values('sales','Scott');
insert into t values('sales','Jimes');
insert into t values('sales','Jack');
insert into t values('account','John');
insert into t values('account','Marry');
insert into t values('hr','Smith');
commit;
方法一：
select dname,WMSYS.WM_CONCAT(ename) ename from t group by dname;
方法二：
SELECT dname, SUBSTR(MAX (SYS_CONNECT_BY_PATH (ename, ',')), 2) NAME
FROM (
SELECT dname, ename, rn, LEAD (rn) OVER (PARTITION BY dname ORDER BY rn) rn1
FROM (SELECT dname, ename, ROW_NUMBER () OVER (ORDER BY ename) rn
FROM t)
)
START WITH rn1 IS NULL
CONNECT BY rn1 = PRIOR rn
GROUP BY dname;