8.8 数据查询 Day 26
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>ANY 大于子查询结果中的某个值
>ALL 大于查询结果全部
Where Sage <ANY (Select Sage 小于某一个学生
from student
Where Sdept = 'SC' )
EXISTS
' true ' or ' false '
当子查询之前为EXISTS 或 NOT EXISTS 时 Select *
union :自动去掉重复元组
union all :保留重复元组
INSERT
into student (Sno,Sname,Ssex,Sdept,Sage)
values ('200215128','陈冬','男','IS',18);
子查询时没有values
update student
Set Sage = 22
Where Sno = '200215121';
Delete
from student
where Sno = '200215128';
Create view
as (as 之后不允许跟order by 和 distinct )
select Sno,Sname,Sage
from student
where Sdept = 'IS' ;
Drop view <视图名>
CASCADE
Drop view IS_S1 CASCADE
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