关于查询当行返回多行
初学不是很懂，SELECT (SELECT answer FROM student1 WHERE student_id=85 ) sbp ,
(SELECT answer FROM student1 WHERE student_id=86 ) dbp
FROM student t_v WHERE enable_flag=1
结果显示单行自查询返回多个行，怎么理解
[解决办法]
--这个Query要干嘛啊...select 的column返回多行肯定报错SELECT (SELECT answer FROM student1 WHERE student_id=85 ) sbp
,(SELECT answer FROM student1 WHERE student_id=86 ) dbp
FROM student t_v
WHERE enable_flag=1
select (
select 2
from dual
) one_
from dual;
select (
select 2
from dual
connect by level<=2
) one_
from dual;
