Tool: cmd sqlplus
Content: basic table operation, plsql programming (branch structure, loop, judgment, etc.)
Account: scott
Preliminary preparation
cmd use tips
Because the author is using sqlplus, and entered in the cmd environment. Text editing in the cmd environment is not easy, so I provide you with a little trick.
As shown in the figure:
cmd shortcut key: alt+space+k to mark the
selected area, enter copy
alt+space+p paste
!!!! Markers can select any range, which is super easy to use compared to the fixed mode of selecting multiple lines in office! ! !
C:\Users\Administrator>sqlplus
SQL*Plus: Release 11.2.0.1.0 Production on Thu Apr 26 08:13:18 2018
Copyright (c) 1982, 2010, Oracle. All rights reserved.
Please enter username: scott
Enter password:
ERROR:
ORA-12560: TNS: protocol adapter error
If you encounter a protocol adapter error, check if the service is enabled.
Please enter username: scott
Enter password:
连接到:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SQL> select * from user_role_privs;
USERNAME GRANTED_ROLE ADM DEF OS_
SCOTT CONNECT NO YES NO
SCOTT RESOURCE NO YES NO
SQL> select sysdate,systimestamp from dual;
SYSDATE
SYSTIMESTAMP
26-Apr-18
26-Apr-18 08.20.24.358000 AM +08:00
text:
SQL> print sname;
SP2-0552: 未声明绑定变量 "SNAME"。
SQL> set serveroutput on
SQL> declare
2 sname varchar2(20) :='abcd';
3 begin
4 sname :=sname||'and tom';
5 dbms_output.put_line(sname);
6 end;
7 /
abcdand tom
PL/SQL 过程已成功完成。
SQL> declare
2 ename varchar2（20） default 'abc';
3 begin
4 select sname into ename from student where sno ='2015
SQL>set serveroutput on
SQL>declare
2 pi constant number :=3.14;
3 r number default 3;
4 area nubmer;
5 begin
6 area :=pi*r*r;
7 dbms_output.put_line(area);
8 end;
9 /
****
PL/SQL 过程已成功完成
SQL>var emp_name varchar2(30);
SQL>begin
2 select sname into : emp_name from student where sno='2018001';
3 end;
4 /
SQL> insert into student values('2018001','zhangsan','男','20');
已创建 1 行。
SQL> select * from student;
SNO SNAME SSEX SAGE
---------- -------------------- -------------------- ----------
2018001 zhangsan 男 20
SQL> var emp_name varchar2(30);
SQL> begin
2 select sname into :emp_name from student where sno='2018001';
3 end;
4 /
PL/SQL 过程已成功完成。
SQL> print emp_name;
EMP_NAME
--------------------------------
zhangsan
----------
//修改scott账户权限
在plsql developer中要是以scott/tiger登录时提示ora-28000 the account is locked。
解决办法：
新装完Oracle10g后，用scott/tiger测试，会出现以下错误提示：
oracle10g the account is locked
oracle10g the password has expired
原因：默认Oracle10g的scott不能登陆。
解决：
（1）conn sys/sys as sysdba; //以DBA的身份登录
（2）alter user scott account unlock;// 然后解锁
（3）conn scott/tiger //弹出一个修改密码的对话框，修改一下密码就可以了
在运行里面输入cmd在DOS模式下输入sqlplus，以system用户名登录，密码是刚装oracle时自己填写的密码orcl，登录进去以后。
SQL> conn sys/sys as sysdba; （分号是必须的但是我是以system登录的所在这不应该写conn sys/sys as sysdba应该写conn system/orcl as sysdba;）
Connected.
SQL> alter user scott account unlock;
User altered.
SQL> commit;
Commit complete.
SQL> conn scott/tiger//请输入新密码，并确认后OK
Password changed
Connected.
----------
SQL> update student set sname='张三' where sno='2018001';
已更新 1 行。
SQL> select * from student;
SNO SNAME SSEX SAGE
---------- -------------------- -------------------- ----------
2018001 张三 男 20
SQL>
SQL> declare
2 myemp student%rowtype;
3 begin
4 select * into myemp from student where sno='2018001';
5 dbms_output.put_line(myemp.sname);
6 end;
7 /
zhangsan
----------
//查询james工资，如果大于900，则发放奖金若干
declare emp.sal % type;
//定义变量，与sal字段类型保持一致
select sal into newSal from emp
where ename='james';
if newSal>900 then
update emp
set comm=800
where ename='james';
end if;
commit;
end;
----------
//if else
SQL> declare
2 newSal emp.sal % type;
3 begin
4 select sal into newSal from emp where ename='ALLEN';
5 if newSal > 1000 then
6 update emp set comm = 800 where ename ='ALLEN';
7 else
8 update emp set comm = 400 where ename ='ALLEN';
9 end if;
10 end;
11 /
PL/SQL 过程已成功完成。
SQL> select * from emp;
ENAME SAL COMM ID
-------------------- ---------- ---------- ----------
SMITH 800
ALLEN 1600 800
WARD 1250 500
JONES 2975
MARTIN 1250 1400
BLAKE 2850
CLARK 2450
SCOTT 3000
KING 5000
TURNER 1500 0
ADAMS 1100
ENAME SAL COMM ID
-------------------- ---------- ---------- ----------
JAMES 950
FORD 3000
MILLER 1300
已选择14行。
----------
//选择结构
SQL> set serveroutput on
SQL>
SQL> declare
2 v_grade char(1):=upper('&grade');
3 begin
4 case v_grade
5 when 'A' then
6 dbms_output.put_line('Excellent');
7 when 'B' then
8 dbms_output.put_line('Very Good');
9 when 'C' then
10 dbms_output.put_line('Good');
11 else
12 dbms_output.put_line('No such grade');
13 end case;
14 end;
15 /
输入 grade 的值: a
原值 2: v_grade char(1):=upper('&grade');
新值 2: v_grade char(1):=upper('a');
Excellent
PL/SQL 过程已成功完成。
----------
//选择结构
SQL> set serveroutput on
SQL> declare
2 v_grade char(1):=upper('&grade');
3 p_grade varchar(20);
4 begin
5 p_grade :=
6 case v_grade
7 when 'A' then
8 'Excellent'
9 when 'B' then
10 'Very Good'
11 when 'C' then
12 'Good'
13 else
14 'No such grade'
15 end;
16 dbms_output.put_line('Grade:'||v_grade||',the result is '||p_grade);
17 end;
18 /
输入 grade 的值: a
原值 2: v_grade char(1):=upper('&grade');
新值 2: v_grade char(1):=upper('a');
Grade:A,the result is Excellent
PL/SQL 过程已成功完成。
----------
//loop循环 计算1+2+3+...+100的和
SQL> set serveroutput on
SQL>
SQL> declare
2 counter number(3):=0;
3 sumResult number:=0;
4 begin
5 loop
6 counter := counter+1;
7 sumResult :=sumResult+counter;
8 if counter>=100 then exit;
9 end if;
10 end loop;
11 dbms_output.put_line('result is:'||to_char(sumResult));
12 end;
13 /
result is:5050
PL/SQL 过程已成功完成。
----------
for循环
SQL> set serveroutput on
SQL> declare
2 counter number(3):=0;
3 sumResult number:=0;
4 begin
5 while counter<100 loop
6 counter:=counter+1;
7 sumResult:=sumResult+counter;
8 end loop;
9 dbms_output.put_line('result is:'||sumResult);
10 end;
11 /
result is:5050
PL/SQL 过程已成功完成。
----------
SQL> set serveroutput on
SQL> declare
2 sumsal emp.sal % type;
3 begin
4 select sum(sal) into sumsal from emp;
5 if sumsal>20000 then
6 goto first_label;
7 else
8 goto second_label;
9 end if;
10 <<first_label>>
11 dbms_output.put_line('ABOVE 20000:'||sumsal);
12 <<second_label>>
13 null;
14 end;
15 /
ABOVE 20000:29025
PL/SQL 过程已成功完成。
----------
SQL> select * from emp;
ENAME SAL COMM ID
-------------------- ---------- ---------- ----------
SMITH 800
ALLEN 1600 800
WARD 1250 500
JONES 2975
MARTIN 1250 1400
BLAKE 2850
CLARK 2450
SCOTT 3000
KING 5000
TURNER 1500 0
ADAMS 1100
ENAME SAL COMM ID
-------------------- ---------- ---------- ----------
JAMES 950
FORD 3000
MILLER 1300
已选择14行。
SQL> select sum(sal) from emp;
SUM(SAL)
----------
29025