存储过程

CREATE [OR REPLACE] PROCEDURE procedure_name
    [ (parameter [,parameter]) ]

IS
    [declaration_section]

BEGIN
    executable_section

[EXCEPTION
    exception_section]

END [procedure_name];

先初始化数据。

create table students
( 
  ID int,
  userName varchar(100),
  userPass varchar(100),
  userAge  int
)
begin
insert into students values(1,'jack','jjjaa',23);
insert into students values(2,'rose','jjjaa',21);
insert into students values(3,'lucy','jjjaa',22);
insert into students values(4,'Tony','jjjaa',24);
end;
commit;

新建一个存储过程，对于某个用户添加年龄

create or replace procedure  SP_Update_Age
(
 uName in varchar,--note,here don't have length ,sql have lenth ,not in oracle.
 Age in int
)
as
begin
    update students set UserAge = UserAge + Age where userName = uName;
    commit;
end SP_Update_Age;  

执行存储过程

call SP_UPDATE_AGE('jack',1);  

call和exec的区别：

1. 但是exec是sqlplus命令，只能在sqlplus中使用；call为SQL命令，没有限制.

2. 存储过程没有参数时,exec可以直接跟过程名（可以省略()），但call则必须带上().

 测试：

set serveroutput on;
declare
       num number;
begin
    num:= -1;
    test(num);
    dbms_output.put_line( 'num = ' || num );
end;

 ifelse:

create or replace procedure Test(x in out number)
is
begin
     if x<0 then
         begin
             x:= 0 - x;
        end;
     elsif x > 0 then     --noted here elsif 
         begin
             x:= x ;
        end;
     else
        x:=    0;
     end if;
end Test;

Test:

set serveroutput on;  --没这句话，看不到dmbs_output信息。
declare
       num number;
begin
    num:= -1;
    test(num);
    dbms_output.put_line( 'num = ' || num );
end;
/******************************
num = 1
PL/SQL procedure successfully completed.
*******************************/

For循环，

For  in ..loop;

set serveroutput on;
DECLARE
   x NUMBER := 100;
BEGIN
   FOR i IN 1..10 LOOP  --noted here 
      IF MOD(i,2) = 0 THEN     -- i is even
          dbms_output.put_line( 'i: '||i||' is even ' );
      ELSE
          dbms_output.put_line('i: '|| i||' is odd' );
      END IF;
      x := x + 100;
      dbms_output.put_line('x value: '|| x);
   END LOOP;
   COMMIT;
END;

/*************************
i: 1 is odd
x value: 200
i: 2 is even 
x value: 300
i: 3 is odd
x value: 400
i: 4 is even 
x value: 500
i: 5 is odd
x value: 600
i: 6 is even 
x value: 700
i: 7 is odd
x value: 800
i: 8 is even 
x value: 900
i: 9 is odd
x value: 1000
i: 10 is even 
x value: 1100
PL/SQL procedure successfully completed.


*************************/

while:

create or replace Procedure Test2(i in out number)
as
begin
     while i < 10 loop
            begin
                   i:= i+1;
           end;
          end loop;
end Test2;

set serveroutput on;
declare
       num number;
begin
    num:= 1;
    test2(num);
    dbms_output.put_line( 'num = ' || num );
end;


/*********************

num = 10
PL/SQL procedure successfully completed.

***********************/