pl/sql练习

创建存储过程出错，可以用show errors查看一下
Warning: Procedure created with compilation errors
SQL> show errors;
Errors for PROCEDURE SCOTT.INSERT_DEPT:
LINE/COL ERROR
-------- -----------------------------------------------------------------------------------------------------------------------------------------------------------------------
2/58 PLS-00103: Encountered the symbol "(" when expecting one of the following: := . ) , @ % default character The symbol ":=" was substituted for "(" to continue.
3/61 PLS-00103: Encountered the symbol "(" when expecting one of the following: := . ) , @ % default character The symbol ":=" was substituted for "(" to continue.

查找存储过程
SQL> select object_name,procedure_name,object_type from user_procedures;
drop procedure proc1;

字符型参数不能加长度，也就是v_dname in varchar2可以，但是v_dname in varchar2（10）会报错
create or replace procedure insert_dept(v_deptno in number,
v_dname in varchar2,
v_loc in varchar2) is
e_dept_err exception;
pragma exception_init(e_dept_err, -0001);
begin
insert into dept values(v_deptno, v_dname, v_loc);
commit;
exception
when e_dept_err then
dbms_output.put_line('You deptno is not unique,please input unique deptno number!');
when others then
dbms_output.put_line('other error');
end;

SQL> exec insert_dept(80,'zhangsan','beijing')
PL/SQL procedure successfully completed
SQL> exec insert_dept(80,'zhangsan','beijing')
You deptno is not unique,please input unique deptno number!
PL/SQL procedure successfully completed

存储过程是带有名称的pl/sql块
包含两种：带参数与不带参数的存储过程
下午：
带有out参数的存储过程
create or replace procedure proc2
(v_empno number,v_ename out varchar2,v_sal out number)
is
begin
select ename,sal into v_ename,v_sal from emp where empno=v_empno;
dbms_output.put_line('Employee name is : '||v_ename||' Employee salary is: '||v_sal);
exception
when no_data_found then
dbms_output.put_line('Employee not exist,please input currect number');
when others then
dbms_output.put_line('other errors');
end;
定义两个参数接收块里的输出参数值
SQL> var v_name varchar2(10);
SQL> var v_salary number;
SQL> exec proc2(7369,:v_name,:v_salary); ----调用系统参数时，前边加:
Employee name is : SMITH Employee salary is: 2600
PL/SQL procedure successfully completed
v_name
---------
SMITH
v_salary
---------
2600
SQL> print v_name
v_name
---------
SMITH
SQL> print v_salary
v_salary
---------
2600

或者用匿名块的方式来执行proc2
declare
v_name emp.ename%type;
v_salary emp.sal%type;
begin
proc2(7369,:v_name,:v_salary);
end;

带有输入和输出型参数的存储过程
create or replace procedure proc3(v_empno in out number,
v_ename out varchar2,
v_sal out number) is
begin
select empno, ename, sal
into v_empno, v_ename, v_sal
from emp
where empno = v_empno;
dbms_output.put_line(v_empno);
dbms_output.put_line(v_ename);
dbms_output.put_line(v_sal);
exception
when no_data_found then
dbms_output.put_line('Employee not exist,please input currect number');
when others then
dbms_output.put_line('other errors');
end;

declare
v_empno emp.empno%type;
v_ename emp.ename%type;
v_sal emp.sal%type;
begin
v_empno:=7369;
proc3(v_empno,v_ename,v_sal);
end;

函数
函数用于返回特定数据
函数作为表达式的一部分被调用
函数可以简化客户端应用程序的开发
提高应用程序的执行性能。

不带有任何参数的函数
create or replace function fun1
return number
is
v_sum_sal emp.sal%type;
begin
select sum(sal) into v_sum_sal from emp where deptno=10;
return v_sum_sal;
end;
declare
v_sumsal emp.sal%type;
begin
v_sumsal := fun1;
dbms_output.put_line(v_sumsal);
end;

升级：
create or replace function fun2
(v_deptno emp.deptno%type)
return number
is
v_sum_sal emp.sal%type;
begin
select sum(sal) into v_sum_sal from emp where deptno=v_deptno;
return v_sum_sal;
end;
declare
v_sumsal emp.sal%type;
begin
v_sumsal := fun2(10);
dbms_output.put_line(v_sumsal);
end;

查询函数情况
select name,text from user_source;

SQL> create or replace function fun2
2
3 (v_empno number , v_ename out varchar2,v_sal out number)
4
5 return number
6
7 is
8
9 begin
10
11 select ename,sal into v_ename,v_sal from emp where empno=v_empno;
12 return v_sal;
13 end;
14 /
Function created
SQL> declare
2
3 v_salary emp.sal%type;
4 v_ename emp.ename%type;
5 v_sal emp.sal%type;
6
7 begin
8 v_salary := fun2(7369,v_ename,v_sal);
9 dbms_output.put_line ('Salary is: '||v_salary);
10
11 end;
12 /
Salary is: 6800
PL/SQL procedure successfully completed

create or replace function fun_sum_sal
(v_empno in number)
return number
is
v_sumsal emp.sal%type;
begin
select (sal+nvl(comm,0))*12 into v_sumsal from emp where empno=v_empno;
return v_sumsal;
end;

declare
v_sumsalary number;
begin
v_sumsalary := fun_sum_sal(7369);
dbms_output.put_line(v_sumsalary);
end;