sqlplus sys/123@222.16.65.250/orcl as sysdba
conn L13209010003/lxh12345@222.16.65.250/orcl
set serveroutput on;
数据库命名：
rename medicine to m_medi;
1）sqlplus kk/12345@localhost/orcl as sysdba
conn lxh/lxh12345@localhost/orcl
2）SQL> create tablespace xinhui
datafile 'c:applxhoradataorclxinhui.dbf' size 100m;
3) create temporary tablespace xinhui1 tempfile
'c:applxhoradataorclxinhui1.dbf'size 100m;
3.5
Create table medicine(
Medicinecode char(10)primary key,
Medicinename varchar(50),
Pycode char(10),
Dosagefrom char(10),standard char(15),
Batchnumber char(20) unique,
Productiondate date,
Expirationdate date,
Category char(10),
Yb char(10))
;
Create table provider(
Providercode char(4) not null,
Providername char(60) not null,
Pycode char(10),address char(50),
Tel char(15),zip char(6),
Email char(30),relation char(8),
Primary key(providercode)
)
;
3.8
Create table pm(
Medicinecode char(10) not null,
Providercode char(4) not null,
Pmdate date not null,
Price number, qyt int,
Primary key(medicinecode,providercode,pmdate),
Foreign key(medicinecode) references medicine(medicinecode),
Foreign key(providercode)references provider(providercode)
);
查看表信息：
select *
from medicine
select *
from provider
select *
from pm
3.17
create cluster index idx_medicine_batchnumber
on medicine(batchnumber)
;
5月14
3.28
Select *
From medicine
Where to_char(productiondate,’yy’,’mm’,’dd’)not between 10-06-06 and 12-01-06
7.23
Create or replace trigger trg_insert_pm
Before insert on pm
For each row
Declare
Mprovidername provider.providername%type;
Bigin
Select providername into m_providername
From provider
Where providercode=:new.provider;
If m_providername='哈药制药' then
Raise_application_error(-2000,'不能插入');
End if;
End;
/
3.35
select*
from provider
where email like 'ttm*_%'escape'*'
;
3.52
select medicine.*,pm.*
from pm right join medicine
on medicine.medicinecode=pm.medicinecode;
3.56
select medicine.*
from medicine
where dosagefrom=
(select dosagefrom
from medicine
where medicinename='小儿颗粒'
)
3.57
select medicinecode,providercode
from pm x
where price>(select avg(price)
from pm y
where y.medicinecode=x.medicinecode
)
3.58
select medicinename
from medicine
where exists
(select *
from pm
where pm.medicinecode=medicine.medicinecode
and providercode='s001'
)
3.59
select distinct providercode from pm pm_a
where not exists
(select *
from pm pm_b
where(medicinecode='10001'or medicinecode='10002')
and not exists
(select *from pm pm_c
where pm_c.providercode=pm_a.providercode
and pm_c.medicinecode=pm_b.medicinecode
)
)
;
3.60
select distinct providercode
from pm pm_a
where not exists
( select*
from medicine
where category='中成药'
)
3.61
select *
from medicine
where dosagefrom='颗粒'
union (all)
select *
from medicine
where category='中药'
;
3.62
select*
from medicine
where dosagefrom='颗粒'
intersect
select*
from medicine
where category='中药'
;
3.63
select*
from medicine
where dosagefrom='颗粒'
except
select*
from medicine
where category='中药'
;
3.73
Create VIEW ISYB_Medicine
As
Select *
From Medicine
Where YB=’是’；
3.74
Create VIEW ISYB_Medicine1
As
Select *
From Medicine
Where YB=’是’
With check option;
3.75
Create view ZJKEB_Medicine
(Medicinecode,Medicinename,Category,Providername)
As
Select Medicine.Medicinecode, Medicine. Medicinename,Category,Providername
From Medicine,PM,Provider
Where Medicine.Medicinecode=PM.Medicinecode
And Provider.Providercode=PM.Providercode
And Provider.Providername=’浙江康恩贝’
With check option;
3.77
Create view ZJKEB_ZCY_Medicine
AS
Select *
From ZJKEB_Medicine
Where Category=’中成药’;
3.77
Create view Proyear_Medicine(Medicinecode,Medicinename,Proyear)
As
Select Medicinecode,Medicinename,to_date(Productiondate)
From Medicine;
3.78
Create view Count_Medicine(Providername,CountM)
As
Select Providername,Count(Medicinecode)
From PM,Provider
Where PM.Providercode=Provider.Providercode
Group by Provider.Providername;
7.17
declare
ex_var1 varchar2(10) default 'pl/sql';
ex_var2 constant number:=16;
med_name medicine.medicinename%type;
m_md medicine%rowtype;
type m_mdt is table of medicine.medicinename%type index by binary_integer;
m_mdt1 m_mdt;
begin
dbms_output.put_line('ex_var1='||ex_var1);
dbms_output.put_line('ex_var2='||ex_var2);
select medicinename
into med_name
from medicine
where medicinecode='10001';
dbms_output.put_line('药品名称='||med_name);
select*
into m_md
from medicine
where medicinecode='10001';
dbms_output.put_line('药品名称:'||m_md.medicinename);
dbms_output.put_line('拼音简码:'||m_md.pycode);
dbms_output.put_line('剂型:'||m_md.dosagefrom);
dbms_output.put_line('规格:'||m_md.standard);
m_mdt1(0):='健儿清解液';
m_mdt1(1):='小儿感冒灵';
dbms_output.put_line(m_mdt1(0));
dbms_output.put_line(m_mdt1(1));
end;
/
set serveroutput on;
7.18
declare
n int;
info varchar2(30);
m_mdatee medicine.expirationdate%type;
begin
select expirationdate
into m_mdatee
from medicine
where medicinename='小儿颗粒';
n:=m_mdatee-sysdate;
case sign(n)
when -1 then info:='已过期';
when 1 then info:='未过期';
else
info:='今天过期';
end case;
dbms_output.put_line('状态::'||info);
for n in 3..6
loop
insert into medicine(medicinecode) values('9000'||n);
end loop;
commit;
end;
/
select medicinecode from medicine where medicinecode like '9000%';
update medicine
set expirationdate='31-12月-16'
where medicinecode='10001';
7.19
declare
m_md medicine%rowtype;
cursor cur_m_md is select* into m_md from medicine;
bigin
if not cur_m_md%isopen then open cur_m_md;
end if;
dbms_output.put_line('提取行数:'||to_char(cur_m_md%rowcount));
loop
fetch cut_m_md into m_md;
dbms_output.put_line('行:'||to_char(cur_m_md%rowcount));
exit when cur_m_md%notfound or cur_m_md%rowcount>=3;
end loop;
close cur_m_md;
end;
/
7.20
declare
cursor cur_medi_name
is
select medicinename from m_medi;
medi_name m_medi.medicinename%type;
result varchar2(200);
begin
open cur_medi_name;
loop
fetch cur_medi_name into medi_name;
exit when cur_medi_name%notfoun;
result:=result||','||medi_name;
end loop;
dbms_output.put_line(result);
close cur_medi_name;
end;
7.21
create or replace produre prc_query_name
(m_code m_medi.medicinecode%type,
m_name out m_medi.medicinename%type)
as
begin
select medicinename into m_name
from m_medi where medicinecode=m_code;
end;
/
declare
m_mdname char(20);
begin
prc_query_mname('10001',m_mdname);
end;
/
7.22
create or replace package pkg_m_medi
as
m_mediname char(20);
procedure prc_query_mname;
end;
/
create or replace package body pkg_m_medi
as
begin
select medicinename into m_medicine from m_medi
where medicinecode='10001';
dbms_output.put_line('药品名称'||m_mediname);
end;
end;
/
begin
pkg_m_medi.prc_query_name;
end;
/
7.23
create or replace trigger trg_insert_pm
before insert on pm
for each row
declare
m_providername provider.providername%type;
begin
select providername into m_providername
from provider
where providercode=:new.providercode;
if m_providername='哈'then
raise_application_error(-20000,'不能插入');
end if;
end;
/
7.25
create or replace trigger trg_update_pm
before update on pm
for each row
declare
m_providername provider.providername%type;
begin
select providername into m_providername
from provider
where providercode=:new.providercode;
if m_providername='海南'and:old.price>=20 and :new.qyt>=300 then
:new.price:=20;
end if;
end;
/
update pm set qyt=300 where providercode='s001'and medicinecode='10003';
7.26
create table record_pm(
medicinecode char(10) not null,
providercode char(4) not null,
pmdate date not null,
qyt int,
primary key(medicinecode,providercode),
foreign key(medicinecode)references m_medi(medicinecode),
foreign key(providercode)references provider(providercode)
)
/
create or replace trigger trg_record_pm
after update on pm
for each row
begin
if :new.qyt<>:old.qyt then insert into record_pm
values(:old.medicinecode,:new.providercode,sysdate,:new.qyt);
end if;
end;
/
9.1
insert into provider(providercode,providername,pycode,address,tel,zip,email,relation)
values('s005','海灵','hlzy','海南','570206','hailing@sina.com','李艳');
1 row inserted
commit;
commit complete
9.2
insert into provider(providercode,providername,pycode,address,tel,zip,email,relation)
增加一列：
alter table T_score add score float;
alter table T_course drop column score;
alter table T_score rename column socre to score;
课程设计一：
1）创建以上几张表，并给表中输入数据。
学生表1 T_STUDENT
create table T_student(
stuno varchar2(16) primary key,
stuname varchar2(16),
stusex varchar2(6),
stubir date
)
课程信息表2 T_COURSE
create table T_course(
courseno varchar2(16) primary key,
coursename varchar2(16),
teano varchar2(16),
foreign key(teano) references T_teacher(teano)
)
教师信息表 3 T_TEACHER
create table T_teacher(
teano varchar2(16) primary key,
teaname varchar2(16),
teatitle varchar2(16)
)
考试成绩表 4 T_SCORE
create table T_score(
stuno varchar2(16),
courseno varchar2(16),
type varchar2(16),
socre float,
primary key(stuno,courseno,type),
foreign key(courseno) references T_course(courseno)
)
2）查询T_STUDENT中所有的数据
select *
from T_student;
3）查询T_STUDENT中所有学生的姓名和性别
select stuname,stusex
from T_student;
4）将学号和姓名显示，其中，姓名的格式为：“姓名：xxx”
select '姓名：'||stuname as " ",stuno
from T_student;
5）为了更好地体现各个学生的考试情况，将T_SCORE中的信息显示，分数显示为与60分的差。
select stuno,courseno,type,score-60
from T_score;
6） 将T_SCORE中的信息显示，分数显示为与60分的差值，列名为“差值”，如果第一条记录分数为空，会得出来什么结果。
(注意：空值具有特殊性，包括空值的任何算术表达式都等于空)
select stuno,courseno,type,score-60 as 差值
from T_score;
7） 将学号和姓名显示，其中，列名分别显示为“学生”和姓名。
select stuno as 学号,stuname as 姓名
from T_student;
8） 将学号和姓名显示在一个列中，列名显示为：信息。
select stuno 信息 from T_student
union
select stuname from T_student;
9） 查询教师的职称种类
select count(distinct teatitle)
from T_teacher;
10） 查询女生的姓名
select stuname
from T_student
where stusex='女';
11） 查询课程VB的信息
select *
from T_course
where coursename='VB';
12） 显示所有期中考试及格的记录
select *
from T_score
where type='期中'and score>=60;
13） 为了找出考试尖子，需要显示所有期末考试在90-100的考试记录（使用<,> between and）
select *
from T_score
where score>90 and score<=100 and type='期末';
select *
from T_score
where score between '90'and '100' and type='期末';
14） 学校要举行一帮一活动，让高分学生帮助低分学生。查询90分以上的期末考试记录，以及不及格的期末考试记录
select *
from T_score
where (score>90 or score<60) and type='期末' ;
15） 利用BETWEEN谓词显示所有期末考试在65-80的考试记录
select *
from T_score
where (score between '65' and '85') and type='期末';
16） 使用IN谓词，显示分数是60,70,80的考试记录
select *
from T_score
where score in (60,70,80)
order by score DESC--降序 ;
17） 查询姓李的学生资料
select *
from T_student
where stuname like '王%';
18） 查询姓“王”，名字为一个字的学生，并将这类学生的详细信息显示出来
select *
from T_student
where stuname like '王_';
19） 查询性别为空的学生资料
select *
from T_student
where stusex is NULL;
20） 用升序显示学生S001的所有期末考试成绩
select score
from T_score
where stuno='S001'and type='期末'
order by score--默认为升序;
21） 用降序显示课程C001的所有期末考试成绩，对于相等的成绩，则按照课程编号升序显示。
select courseno,score
from T_score
where courseno='C001' and type='期末'
order by score DESC;
22） 查询姓名为“郭莉芳”的考试成绩
select*
from T_score
where stuno=(
select stuno
from T_student
where stuname='郭莉芳'
);
23） 显示各个教师及其讲授课程的详细情况
select T_teacher.teaname,T_course.*(这两个顺序有关)
from T_teacher right join T_course
on T_teacher.teano=T_course.teano;
24） 查询名为“梁天”的教师没有上过的课程。
select coursename
from T_course
where not exists(
select *
from T_teacher
where T_course.teano=T_teacher.teano and teaname='梁天'
);
25） 课程“大学物理”，有哪些学生选过？请列出这些学生的姓名
select stuname
from T_student
where stuno=(
select stuno
from T_score
where courseno=(
select courseno
from T_course
where coursename='大学物理'
)
);
26） 查询学号为”S002”的学生，参加课程“C001”考试的成绩，显示格式为：
期中成绩 期末成绩 总评成绩
其中，总评成绩=期中成绩*0.4+期末成绩*0.6
select x.score as 期中成绩,y.score as 期末成绩,x.score*0.4+y.score*0.6 as 总评成绩
from T_score x ,T_score y
where x.stuno='S002' and y.stuno='S002'and x.type='期中' and y.type='期末' and x.courseno='C001' and y.courseno='C001';
27） 查询课程“大学物理”是哪一位老师教的，列出其姓名
select T_teacher.teaname,T_course.coursename
from T_teacher ,T_course
where T_teacher.teano in (
select teano
from T_course
where coursename='大学物理') and T_course.coursename='大学物理';
28） 使用左外连接完成27）
select T_teacher.teaname,T_course.coursename
from T_teacher left join T_course
on T_teacher.teano in (
select teano
from T_course
where coursename='大学物理') and T_course.coursename='大学物理';
29） 使用右外连接完成27）
select T_teacher.teaname,T_course.coursename
from T_teacher right join T_course
on T_teacher.teano in (
select teano
from T_course
where coursename='大学物理') and T_course.coursename='大学物理';
30） 查询T_STUDENT内所有人的姓名和性别
select stuname,stusex
from T_student;
31） 将学号和姓名用下划线连接，显示在一列。
select stuname||'_'||stuno as " "
from T_student;
32） 显示教授的所有资料
select *
from T_teacher,T_course
where T_teacher.teatitle='教授' and T_teacher.teano=T_course.teano;
33） 显示姓张的男生的姓名
select stuname
from T_student
where stuname like '王%';
34） 将所有的分数显示为与60分的差值，同时也显示原分数。
select score,score-60 as 与60分的差值
from T_score;
35） 查询高级职称以下的教师姓名，高级职称以下为副教授和讲师
select teaname,teatitle
from T_teacher
where teatitle in ('副教授','讲师')
order by teatitle;
36） 学校需要请学生对教授的教学作评价，因此需要通知相关学生。请查询出：教授所教过的课程，有哪些学生选过？列出他们的姓名
select distinct T_teacher.teaname, T_student.stuname,T_course.coursename
from T_teacher,T_student,T_course,T_score
where T_teacher.teatitle='教授' and T_teacher.teano=T_course.teano and T_score.courseno=T_course.courseno and T_score.stuno=T_student.stuno
order by T_teacher.teaname;
37） 查询郭莉芳的哪些科目期末考试没有及格？列出这些科目的名称和分数
select T_course.coursename,T_score.score
from T_course,T_score,T_student
where T_student.stuname='郭莉芳' and T_score.score<60 and T_course.courseno=T_score.courseno and T_student.stuno=T_score.stuno and T_score.type='期末';
38） 统计学生姓名的数量
select count(stuname)
from T_student;
39） 查询学校有多少名教师
select count(teaname)
from T_teacher;
40） 查询为“梁天”的教师讲了多少门课
select count(teano)
from T_course
where teano=(
select teano
from T_teacher
where teaname='梁天'
);
41） 查询参加过考试的学生数量
select count(distinct stuno)
from T_score;
42） 查询郭莉芳选了多少门课
select count(distinct T_score.courseno) as 郭莉芳选课门数
from T_score,T_student
where T_score.stuno=T_student.stuno and T_student.stuname='郭莉芳';
43） 查询课程C002的期末考试平均分
select AVG(T_score.score) as 课程C002的期末考试平均分
from T_score,T_course
where T_course.courseno=T_score.courseno and T_course.courseno='C002' and T_score.type='期末';
44） 查询课程C003的期中考试总分
select SUM(distinct T_score.score) as 课程C003的期中考试总分
from T_score,T_course
where T_course.courseno=T_score.courseno and T_course.courseno='C003' and T_score.type='期中';
45） 查询学校所有考试记录的总分
select sum(score)
from T_score;
46） 查询课程C004的期末考试最高分
select max(T_score.score)
from T_score,T_course
where T_score.type='期末' and T_score.courseno=T_course.courseno and T_course.courseno='C004';
47） 查询每个教师讲授的课程数量，并将其姓名和课程数量显示出来
select T_teacher.teaname as 教师,count(T_course.teano) as 课程数量
from T_teacher left join T_course
on T_teacher.teano=T_course.teano
group by T_teacher.teaname;
48） 查询郭莉芳每门课的平均分，显示课程名称和平均分
select T_course.coursename as 课程,AVG(T_score.score) as 平均分
from T_course,T_score,T_student
where T_student.stuno=T_score.stuno and T_score.courseno=T_course.courseno and T_student.stuname='郭莉芳'
group by T_course.coursename;
49） 学校要查询哪门课的授课效果最好，请查询各门课程平均分的最大值
做法1:
select AVG(T_score.score) as 各门课程平均分的最大值
from T_score,T_course
where T_score.courseno in
(select courseno
from(select courseno,AVG(score), rank()over(order by avg(score) desc)k
from T_score
group by courseno)
where k=1);
做法2:
select max(avg(score)) as 各门课程平均分的最大值
from T_score
group by courseno
having avg(score) in
(select avg(score)
from T_score
group by courseno
);
50） 向T_TEACHER表中添加一条记录，教师编号为T009,教师姓名为汤路名，职称为教授
insert into T_teacher
values('T008','汤路名','教授');
51） 由于有些学生表现比较优秀，拟将其升级为教师。向T_TEACHER表中添加一些记录，这些记录为：平均分75分以上的学生和学号、姓名，他们的职称为助教
insert into T_teacher
select stuno,stuname,'助教'
from T_student
where stuno in (
select stuno
from T_score
group by stuno
having AVG(score)>=75
);
delete
from T_teacher
where teano='S002';
52） 删除T_STUDENT表中的女生记录
delete
from T_student
where stusex='女';
53） 删除T_COURSE表中的全部记录
先新建一张表:
create table T_course1(courseno varchar2(16),coursename varchar2(16),teano varchar2(16));
delete
from T_course1;
54） 删除女生的分数记录
delete
from T_score
where T_score.stuno in (select T_score.stuno
from T_student,T_score
where T_score.stuno=T_student.stuno and T_student.stusex='女'
);
S005 C002 期末 60
55） 将所有的学生分数增加5分
update T_score
set score=score+5;
56） 将所有的学生分数增加5分，类型变为“正常考试”
update T_score
set score=score+5,type='正常考试';
57） 将所有女生的性别变为GIRL
update T_student
set stusex='GIRL'
where stusex='女';
58） 创建一个员工工资表，包含各个员工的编号、姓名、性别、出生年月、工资。性别为默认“男”。编号为主键。
create table wage(num varchar(20) primary key,name varchar(20),sex char(5) default '男',bir date,salary number);
59） 将54创建的员工工资表改名；
alter table wage rename to wages;
60） 创建一个员工工资表，包含各个员工的编号、姓名、性别、出生年月、工资。其中，员工的编号来自所有学生的学号，员工的姓名来自所有学生姓名，员工的性别来自学生性别，出生年月来自学生的出生年月，工资为0
（利用：CREATE TABLE 表名【列名1（，列名2…..）】
AS
子查询 ）
create table wage(num primary key,name,sex,bir,salary)
as
select stuno,stuname,stusex,stubir,'0'
from T_student;
61） 在T_TEACHER表中增加性别和出生年月列
alter table T_teacher
add (sex char(10),bir date);
62） 在T_TEACHER表中删除性别和出生年月列
alter table T_teacher
drop (sex,bir);
63） 在T_TEACHER表中，将TEANAME重命名为“教师姓名”
alter table T_teacher
rename column 教师姓名 to teaname;
64） 在T_TEACHER表中，将TEATITLE的数据类型改为VARCHAR2(30)
alter table T_teacher
modify(teatitle varchar2(30));
65） 创建一个员工工资表，包含各个员工的编号、姓名、性别、出生年月、工资。编号和姓名组合为主键。
create table wage2(num varchar(20),name varchar(20),sex char(5) default '男',bir date,salary number,
primary key(num,name)
);
66） 创建一个员工工资表，包含各个员工的编号、姓名、性别、出生年月、工资。编号为主键,姓名唯一
create table wage66(num varchar(20) primary key,name varchar(20) unique,sex char(5) ,bir date,salary number);
67） 将T_STUDENT表中的STUNAME指定为唯一性约束
alter table T_student
add constraint stuname
unique(stuname);
68） 将65题中指定的唯一性约束删除
alter table T_student
drop constraint stuname;
69） 创建一个员工工资表，包含各个员工的编号、姓名、性别、出生年月、工资。编号为主键,性别只能是男或者女
create table wage69(num varchar(20) primary key,name varchar(20),sex varchar2(10) check(sex in('男','女')),bir date,salary number);
70） T_SCORE中的分数，要求在0-100之间
alter table T_score
add constraint score check(score between 0 and 100);
71） 为T_STUDENT的STUNAME建立索引
create index idx_stuname on T_student(stuname);
72） 删除71题建立的索引
drop index idx_stuname;
73） 女生部长关心女生的信息，请将女生信息创建为一个视图
create view female
as
select T_student.*,T_score.courseno,T_score.type,T_score.score
from T_student right join T_score
on T_student.stuno=T_score.stuno;
drop view glf;
74） 郭莉芳关心自己参加考试的课程编号、名称和考试平均成绩，请建立视图
create view glf(courseno,coursename,score)
as
select T_course.courseno,T_course.coursename,AVG(score)
from T_score , T_course,T_student
where T_student.stuname='郭莉芳' and T_student.stuno=T_score.stuno
and T_course.courseno=T_score.courseno
group by T_course.courseno,T_course.coursename;
75） 将全校的学生分数平均数查出来，存储在变量avascore内并打印
declare
avascore T_score.score%type;
begin
select avg(score) into avascore
from T_score;
dbms_output.put_line('平均值是： '||avascore);
end;
/
76） 定义一个表变量stunames,请将几名学生的姓名放入，并打印
declare
stunames T_student%rowtype;
result T_student.stuname%type;
cursor cur_name is
select stuname into stunames.stuname
from T_student;
begin
if not cur_name%isopen
then open cur_name;
end if;
loop
fetch cur_name into result;
exit when cur_name%notfound;
dbms_output.put_line('姓名是： '||result);
end loop;
close cur_name;
end;
/
77） 查询郭莉芳的所有科目平均成绩，决定她的等级。90-100为优秀，70-89为良好，
60-69为及格，其他为差。请将其分数和等级打印出来。
select avg(score),decode(sign(avg(score)-90),1,'优秀',0,'优秀',-1,
decode(sign(avg(score)-70),1,'良好',0,'良好',-1,
decode(sign(avg(score)-60),1,'及格',0,'及格',-1,'不及格')))
from T_score,T_student
where T_student.stuname='郭莉芳' and T_score.stuno=T_student.stuno;
78） 编写存储过程，打印全校所有学生平均分
create or replace procedure p_score
(tt_stuno t_score.stuno%type,
tt_score out t_score.score%type)
as
begin
select avg(score) into tt_score
from t_score where stuno=tt_stuno;
end;
/
declare
ttt_score varchar2(50);
begin
p_score('S001',ttt_score);
dbms_output.put_line('平均成绩是：'||ttt_score);
end;
/
79） 编写一个存储过程，输出一个学生的学号，将这个学生所选的课程的数量、所有课程的平均分存储在两个输出参数内
create procedure pro790(sl,ag,cur_out cursor)
as
begin
open cur_out for
select T_student.stuno,count(T_score.stuno)
from T_score,T_student
where T_student.stuno=T_score.stuno;
end;
/
80） 修改某门课程的任课教师。如果任课教师室教授，不可以进行修改
create or replace
trigger cc
Before update on t_course
For each row
Declare
tea_title t_teacher.teatitle%type;
Begin
Select teatitle into tea_title from t_teacher
Where teano=:old.teano;
if tea_title='教授' then
RAISE_APPLICATION_ERROR(-20000, '是教授，不能修改表');
End if;
End;
/
验证
update t_course
set teano='T009'
where teano='T003';
81） 显示教授的姓名，用空格隔开，保存在一个字符串内，打印。
set serveroutput on
declare
cursor cur_name
is
select teaname from T_TEACHER
WHERE t_teacher.TEATITLE='教授';
medi_name T_TEACHER.TEATITLE%type;
result varchar2(200);
begin
open cur_name;
loop
fetch cur_name into medi_name;
exit when cur_name%notfound;
result:=result||' '||medi_name;
end loop;
dbms_output.put_line(result);
close cur_name;
end;