plsql中的procedure和function编程

procedure:存储过程

eg:

 

create or replace procedure p   --这儿是和plsql的区别

        is

        cursor c

        is 

            select * from emp2 for  update;

        --v_temp c%rowtype;

 

begin

 

        for v_temp in c 

            loop 

                    if(v_temp.sal< 2000) then

                        update emp2 set sal=sal*2 where current of c ;

                    elsif(v_temp.sal = 5000) then

                        delete from emp2  where current of c;

                    end if;

            end loop;

            commit;

end;

 

执行过程的命令：exec p;    begin p end;

 

带参数的存储过程；

create or replace procedure p   --in表示传入参数 out传出参数，

        (v_a in number,v_b number ,v_ret out number,v_temp in out number)

is

 

begin 

        if(v_a > v_b) then

                v_ret := v_a;

        else

            v_ret := v_b;

        end if;

    v_temp := v_temp+1;

end;

 

调用过程：

declare 

        v_a number := 3;

        v_b number := 4;

        v_ret number ;

        v_temp number := 5;

 

begin

            p(v_a,v_b,v_ret,v_temp);

            dbms_output.put_line(v_ret);

            dbms_output.put_line(v_temp);

end;

 

函数：function

 

create or replace  function sal_tax

        (v_sal number)   --声明了一个函数

        return number

is 

begin

        if(v_sal < 2000) then

                return 0.10;

        elsif(v_sal < 2750) then

                return 0.15;

        else

                return 0.20;

        end if;

end;

 

函数的调用：：select lower(ename),sal_tax(sal) from emp;

 

触发器：trigger 

不能直接执行，依赖于表

create table emp2_log

(

    uname varchar2(20),

    action varchar2(10),

    atime date

);

 

创建触发器

 

create or replace trigger trig

        after insert or delete or update on emp2 for each row

begin

        if inserting then

            insert into emp2_log values (USER,'insert',sysdate);

        elsif updating then

            insert into emp2_log values(USER,'update',sysdate);

        elsif   deleting then

            insert into emp2_log values (USER,'delete',sysdate);

        end if;

end;

 

update emp2 set sal=sal*2 where deptno = 30;

 

drop triggle trig;(删除)

 

create  or replace trigger    trig

        after update on dept

        for each row 

begin 

        update emp set deptno =:NEW.deptno where deptno = :OLD.deptno;

end;

 

update dept set deptno = 99 where deptno = 10;

 

树状结构的存储于显示：

 

create table ariticle

(

            id number primary key,

            cont varchar2(4000),

            pid number,

            isleaf number(1), -- 0代表非叶子节点，1代表叶子节点

            alevel number(2)

);

 

insert into ariticle values(1,'ahshdhshd',0,0,0);

insert into ariticle values(2,'bhshdhshd',1,0,1);

insert into ariticle values(3,'chshdhshd',2,1,2);

insert into ariticle values(4,dhshdhshd',2,0,2);

insert into ariticle values(5,'ehshdhshd',4,1,3);

insert into ariticle values(6,'fhshdhshd',10,1);

insert into ariticle values(7,'ghshdhshd',6,1,0);

insert into ariticle values(8,'hhshdhshd',3,0,4);

insert into ariticle values(9,'ihshdhshd',7,0,0);

insert into ariticle values(10,'jhshdhshd',9,0,3);

 

commit;(提交)

 

 

 

create or replace procudure p (v_pid ariticle.pid%type,v_level binary_integer)

is cursor c 

    is select * from ariticle where pid = v__pid;

    v_preStr varchar2(1024) :='';

begin 

    for i in 0..v_level loop

        v_preStr :=v_preStr || '       ';

        for v_ariticle in c 

        loop

        dbms_output.put_line(v_preStr || v_ariticle.cont);

           if (v_ariticle.isleaf = 0) then

                p(v_ariticle.id,v_level+1);

            end if;

        end loop;

end;

 

exec p(0);

 

转载至：http://blog.csdn.net/zhaoming262350/article/details/8929878?utm_source=tuicool

转载至：http://blog.csdn.net/zhaoming262350/article/details/8929878?utm_source=tuicool

转载至：http://blog.csdn.net/zhaoming262350/article/details/8929878?utm_source=tuicool