Oracle存儲過程案例詳解

-- Create table
create table EMP
(
  empno    NUMBER(4) not null,
  ename    VARCHAR2(10),
  job      VARCHAR2(9),
  mgr      NUMBER(4),
  hiredate DATE,
  sal      NUMBER(7,2),
  comm     NUMBER(7,2),
  deptno   NUMBER(2)
)

create or replace procedure firstP(name in varchar2) is
/*這裡name為的參數,in為輸入,varchar2為類型*/
begin
 /* dbms_output.put_line(); 相當輸出到控制臺上,這樣我們一個簡單的存儲過程就完成啦
 記住一句話的結束使用分號結束,存儲過程寫完一定要執行
 將它保存到數據庫中 (F8)快捷鍵,或者點擊左上角執行*/
  dbms_output.put_line('我的名字叫'||name);/*dbms_output.put_line相當於JAVA中的System.out.println("我的名字叫"+name);*/
end firstP;

-- Created on 2018/12/30 星期日 by ADMINISTRATOR 
declare 
  -- Local variables here
  /*測試名稱 名稱類型 使用 := 給參數賦值,在多說一句,分號結束本句*/
  name2 varchar2(64):='數據庫';
begin
  -- Test statements here
  firstp(name2);
end;

create or replace procedure isifp(age in number) is
/*存儲過程if判斷以then開始,以end if; 結束*/
begin
  if (age > 30) then
    dbms_output.put_line('我已經超過30歲瞭');
  else
    if (age < 10) then
      dbms_output.put_line('我還是個兒童');
    else
      dbms_output.put_line('我正在奮鬥時期');
    end if;
  end if;

end;

create or replace procedure inandout(name in varchar2, age in number,outp out varchar2) is
/*in 代表輸入,out 代表輸出*/
begin
  outp:='my name is '|| name ||',my age is '||age;/*相當於JAVA中的return outp,但是請註意,存儲過程中可以return多個值*/
end inandout;

-- Created on 2018/12/30 星期日 by ADMINISTRATOR 
declare 
  -- Local variables here
  name varchar2(64):='數據庫';
  age number:=06;
  out_p varchar2(64);
begin
  -- Test statements here
  inandout(name,age,outp=>:out_p);
  /*這裡的outp是存儲過程中的輸出參數,out_p是在測試中使用的別名*/
end;

create or replace procedure sysrefcursor(id in number, columnss out sys_refcursor) as
/*columnss out sys_refcursor  為輸出遊標*/
begin
  open columnss for
  select * from emp where empno=id;
end;

-- Created on 2018/12/30 星期日 by ADMINISTRATOR 
declare 
  -- Local variables here
 cursor ee is select * from emp where empno=7934;
begin
  -- Test statements here
  for e in ee loop
  dbms_output.put_line('deptno:'||e.deptno);
  end loop;
end;

-- Created on 2018/12/30 星期日 by ADMINISTRATOR 
declare 
  -- Local variables here
 cursor ee is select * from emp where empno=7934;
 cur ee % rowtype;
begin
  -- Test statements here
  open ee;
  loop
  fetch ee into cur;
  exit when ee%notfound;
  dbms_output.put_line('name:'||cur.ename);
  end loop;
  close ee;
end;

-- Created on 2018/12/30 星期日 by ADMINISTRATOR 
declare 
  -- Local variables here
 cursor ee is select * from emp where job='CLERK';
begin
  -- Test statements here
  for e in ee loop
  dbms_output.put_line('deptno:'||e.deptno);
  end loop;
end;

create or replace procedure intop(id in number, print2 out varchar2) as
  e_name varchar2(64);
begin
  select ename into e_name from emp where empno = id;
  if e_name ='ALLEN' then 
   dbms_output.put_line(e_name);
   print2:='my name is '||e_name;
   else if e_name ='SMITH' then 
      print2:='打印sql'||e_name;
      else
        print2:='打印其他';
      end if;
   end if;
end intop;

-- Create table
create table CLASSES
(
  id       NUMBER not null,
  name     VARCHAR2(14),
  classesc VARCHAR2(10),
  seq      NUMBER(5)
)
tablespace USERS
  pctfree 10
  initrans 1
  maxtrans 255
  storage
  (
    initial 64K
    next 1M
    minextents 1
    maxextents unlimited
  );
-- Create/Recreate primary, unique and foreign key constraints 
alter table CLASSES
  add constraint PK_CLASSES primary key (ID)
  using index 
  tablespace USERS
  pctfree 10
  initrans 2
  maxtrans 255
  storage
  (
    initial 64K
    next 1M
    minextents 1
    maxextents unlimited
  );

-- Create sequence 
create sequence SEQ_CLASSES
minvalue 1
maxvalue 9999999999999999999999999999
start with 2
increment by 1
cache 20;

create or replace procedure proclasses(Names     in varchar2,
                                       classescs in varchar) as
/*在我們創建存儲過程的時候as其實是is*/
  id  number;/*設置變量名稱*/
  c   number;
  seq number;
begin
  select SEQ_CLASSES.nextval into id from dual;/*獲取下一個序列,使用into賦值給id這個變量名稱*/
  dbms_output.put_line('classescs=' || classescs);/*打印而已*/
  select count(*) into c from Classes where classesc = classescs;/*條件判斷,classesc=進來的變量*/
  if (c > 0) then/*當數量大於0時*/
    select max(seq) + 1 into seq from Classes where classesc = classescs;
    dbms_output.put_line('第一個seq' || seq);
  else
    if (c = 0) then
      seq := 0;/*如果查詢出來的數量為0的時候,我們賦值seq變量為0*/
      dbms_output.put_line('c=0的時候seq' || seq);
    end if;
  end if;
  insert into classes
    (id, name, classesc, seq)
  values
    (id, names, classescs, seq);
 /*insert插入這個不用多說瞭,大傢都明白;註意的是我們insert之後一定要提交。
  不然數據沒有持久化到數據庫，這個insert沒有任何意義瞭*/
end proclasses;

-- Created on 2019/1/7 星期一 by ADMINISTRATOR 
declare 
  -- Local variables here
  names varchar2(32):='曉明';
  classescs varchar2(32):='一班';
begin
  -- Test statements here
  proclasses(names,classescs);
end;