Oracle 创建Package Procedure Function

一.创建程序包规范实例：

create or replace package pack_op is

         procedurepro_print_ename(id number,value2 out number);

         procedurepro_print_sal(id number);

         functionfun_re_date(id number) return date;

end pack_op;

创建程序包主体：

create or replace package body pack_op is

         procedure pro_print_ename(id number,value2 out number) is/as

         name emp.ename%type;

         begin

             select ename into name from emp whereempno=id;

                   dbms_output.put_line('职员姓名：'||name);

                   value2:= 500;

         Exception

                   Whenothers then

                      Rollback;

         end pro_print_ename;

        

         procedure pro_print_sal(id number) is/as

         salaryemp.sal%type;

         begin

                   selectsal into salary from emp where empno=id;

                   dbms_output.put_line('职员工资：'||salary);

         Exception

                   When others then

                     Rollback;

         end pro_print_sal;

        

         function fun_re_date(id number) return date is/as

         bedateemp.hiredate%type;

         begin

                   select hiredate into bedate from emp where empno=id;

         returnbedate;

         end fun_re_date;

end pack_op;

调用程序包中创建的过程和函数
declare value2 number;(如果赋值value2 number :=100; value2就是in out类型)

         begin

         pack_op.pro_print_ename(7900,value2);

         dbms_output.put_line(value2);

end;

exec pack_op.pro_print_sal(7900);

select pack_op.fun_re_date(7900) from dual;

查询有关过程、函数和程序包的信息：USER_OBJECTS数据字典视图

column object_name format a18

select object_name,object_type fromuser_objects

      where object_type in ('PROCEDURE','FUNCTION','PACKAGE','PACKAGE BODY');

二.创建带OUT参数的过程(默认是 in,输入输出in out)

create or replace procedure test(value1varchar2,value2 out number) is

identity number;

begin

         select sal into identity from emp where empno=value1;

         if identity<2000 then value2:=1000;

         else value2:=500;

         end if;

end test;

调用带OUT参数的过程：(value2 number := 100--相当于in out)

declare value2 number;

         begin

         test(7900,value2);

         dbms_output.put_line(value2);

end;
将过程的执行权限授予其他用户

GRANT EXECUTE ON find_emp TO scott;  GRANT EXECUTE ON swap TO PUBLIC;

将find_emp过程的执行权限授予给用户scott，将执行swap过程的权限授予所有数据库用户。

删除过程语法：DROP PROCEDURE procudure_name;

注意事项：

1.存储过程参数不带取值范围,in表示传入,out表示输出,in out两者都(传入最大值4000)

2.变量带取值范围，后面接分号--定义变量最大值32767

3.在判断语句前最好先用count(*)函数判断是否存在该条操作记录

4.用select 。。。into。。。给变量赋值

5.在代码中抛异常用 raise+异常名

三.创建函数

1)有返回值无参数

create or replace function fun_hello

return varchar2

is/as

begin

         return'朋友，您好';

end fun_hello;

调用函数：select fun_hellofrom dual;

2)默认 in 型参数

create or replace function get_sal(dept_idnumber)

return number//返回number类型

as

v_sumsal number(10) := 0;

cursor salary_cursor is select salary fromemployees where department_id = dept_id;

begin

for c in salary_cursor loop

v_sumsal := v_sumsal +c.salary;

end loop;

return v_sumsal;

end;

调用方式一

begin

dbms_output.put_line(get_sal(80));

end;

调用方式二

select get_sal(80) from dual;

3)带有 out 型参数

create or replace function get_salsum(dept_id number,total_count out number)

//total_count为 out 型参数

return number

as

v_sumsal number(10) := 0;

cursor salary_cursor is select salary fromemployees where department_id = dept_id;

begin

//为total_count赋初值 0;

total_count := 0;

for c in salary_cursor loop

v_sumsal := v_sumsal +c.salary;

total_count := total_count + 1;

end loop;

return v_sumsal;

end;

调用方式
declare

v_num number(10);(v_num number := 100--相当于in out)

begin

dbms_output.put_line(get_salsum(80,v_num));

dbms_output.put_line(v_num);

end;

形式参数必须只使用数据库类型，不得使用PL/SQL类型。函数的返回类型也必须是数据库类型
删除函数：DROP FUNCTIONfunction_name;

会遇到的小问题：select into问题

SELECT INTO STATEMENT将select查询的结果存入到变量中，可以同时将多个列存储多个变量中，
必须有一条记录，否则抛出异常(如果没有记录抛出NO_DATA_FOUND)

解决办法：

BEGIN

SELECT name

  into v_name

  FROM t_student

 WHERE id = '101'

EXCEPTION

WHEN NO_DATA_FOUND THEN

  v_name := '';

  WHEN OTHERS THEN

  v_name := '多于一条啦';

END;