Oracle增删改

--相表中插入一条数据
INSERT INTO "Grade"("GradeID","GradeIdName")
values(1,'20级中职');


--如果按序插入，可以省略字段列表
INSERT INTO "Grade"
values(2,'19级中职');


--插入多条数据记录
insert all
into "Grade" values(3,'18级中职')
into "Grade" values(4,'17级中职')
into "Grade" values(5,'16级中职')
select 1 from dual;


--插入默认值
insert into "Grade"
values(6,default);


--创建电话号码表PhoneList
create table "PhoneList"(
"StudentNo" number(11) not null,
"StudentName" VARCHAR2 (20) not null,  
"Sex" char(2) not null,
"Phone" VARCHAR2(20) not null
);


---从原表Student中抽取字段插入到PhoneList中
insert into "PhoneList"("StudentNo","StudentName","Sex","Phone")
select "StudentNo","StudentName","Sex","Phone"
from "Student";


--更新记录，将学生表的第二个学生密码修改为8888
update "Student"
set "LoginPwd"='8888'
where "StudentNo"=2;


--更新记录，将95分及以下的学生成绩全部+5
update "Result"
set "StudentResult"="StudentResult"+5,"SubjectNo"=4
where "StudentResult"<=95;


--更新记录，将QQ邮箱为空的学生表的邮箱改为aaaqq.com
update "Student"
set "Email"='aaaqq.com'
where "Email" is null;  --is null：为空    is not null：不为空


--删除记录
delete from "Student"
where "StudentNo"=3;


--清空表数据，保留表结构，删除的数据不可恢复，慎用！
truncate table "Student";