-- 声明游标；CURSOR cursor_name IS select_statement


--For 循周游标

--（1）定义游标

--（2）定义游标变量

--（3）行使for轮回来行使这个游标
declare

       --典范定义
       cursor c_job

       is

       select empno,ename,job,sal

       from emp

       where job="MANAGER";

       --定义一个游标变量v_cinfo c_emp%ROWTYPE ，该典范为游标c_emp中的一止数据典范
       c_row c_job%rowtype;

begin

       for c_row in c_job loop

         dbms_output.put_line(c_row.empno||"-"||c_row.ename||"-"||c_row.job||"-"||c_row.sal);

       end loop;

end;





      

--Fetch游标

--行使的时间必须要明确的挨开战封闭


declare 

       --典范定义
       cursor c_job

       is

       select empno,ename,job,sal

       from emp

       where job="MANAGER";

       --定义一个游标变量
       c_row c_job%rowtype;

begin

       open c_job;

         loop

           --提取一止数据到c_row
           fetch c_job into c_row;

           --判读可否提取到值，没取到值就退出
           --取到值c_job%notfound 是false 
           --取没有到值c_job%notfound 是true
           exit when c_job%notfound;

            dbms_output.put_line(c_row.empno||"-"||c_row.ename||"-"||c_row.job||"-"||c_row.sal);

         end loop;

       --封闭游标
      close c_job;

end;



--1：肆意施止一个update操纵，用隐式游标sql的属性%found,%notfound,%rowcount,%isopen考查update语句的施止环境。
       begin

         update emp set ENAME="ALEARK" WHERE EMPNO=7469;

         if sql%isopen then

           dbms_output.put_line("Openging");

           else

             dbms_output.put_line("closing");

             end if;

          if sql%found then

            dbms_output.put_line("游标指向了有效止");--断定游标可否指向有效止
            else

              dbms_output.put_line("Sorry");

              end if;

              if sql%notfound then

                dbms_output.put_line("Also Sorry");

                else

                  dbms_output.put_line("Haha");

                  end if;

                   dbms_output.put_line(sql%rowcount);

                   exception 

                     when no_data_found then

                       dbms_output.put_line("Sorry No data");

                       when too_many_rows then

                         dbms_output.put_line("Too Many rows");

                         end;

declare

       empNumber emp.EMPNO%TYPE;

       empName emp.ENAME%TYPE;

       begin

         if sql%isopen then

           dbms_output.put_line("Cursor is opinging");

           else

             dbms_output.put_line("Cursor is Close");

             end if;

             if sql%notfound then

               dbms_output.put_line("No Value");

               else

                 dbms_output.put_line(empNumber);

                 end if;

                 dbms_output.put_line(sql%rowcount);

                 dbms_output.put_line("-------------");

                 

                 select EMPNO,ENAME into  empNumber,empName from emp where EMPNO=7499;

                 dbms_output.put_line(sql%rowcount);

                 

                if sql%isopen then

                dbms_output.put_line("Cursor is opinging");

                else

                dbms_output.put_line("Cursor is Closing");

                end if;

                 if sql%notfound then

                 dbms_output.put_line("No Value");

                 else

                 dbms_output.put_line(empNumber);

                 end if;

                 exception 

                   when no_data_found then

                     dbms_output.put_line("No Value");

                     when too_many_rows then

                       dbms_output.put_line("too many rows");

                       end;

                   

                 

       

--2,行使游标战loop轮回来显现所有部份的称呼

--游标声明
declare 

       cursor csr_dept

       is

       --select语句
       select DNAME

       from Depth;

       --指定止指针,这句话该当是指定战csr_dept止典范沟通的变量
       row_dept csr_dept%rowtype;

begin

       --for轮回
       for row_dept in csr_dept loop

           dbms_output.put_line("部份称呼:"||row_dept.DNAME);

       end loop;

end;





--3,行使游标战while轮回来显现所有部份的的天理位置（用%found属性）
declare

       --游标声明
       cursor csr_TestWhile

       is

       --select语句
       select  LOC

       from Depth;

       --指定止指针
       row_loc csr_TestWhile%rowtype;

begin

  --挨开游标
       open csr_TestWhile;

       --给第一止喂数据
       fetch csr_TestWhile into row_loc;

       --测试可否无数据，并施止轮回
         while csr_TestWhile%found loop

           dbms_output.put_line("部份所在："||row_loc.LOC);

           --给下一止喂数据
           fetch csr_TestWhile into row_loc;

         end loop;

       close csr_TestWhile;

end; 

select * from emp







       

--4,采用用户输进的部份编号，用for轮回战游标，挨印出此部份的所有雇员的所有信息(行使循周游标)

--CURSOR cursor_name[(parameter[,parameter],...)] IS select_statement;

--定义参数的语法如下:Parameter_name [IN] data_type[{:=|DEFAULT} value]  


declare 

      CURSOR 

      c_dept(p_deptNo number)

      is

      select * from emp where emp.depno=p_deptNo;

      r_emp emp%rowtype;

begin

        for r_emp in c_dept(20) loop

            dbms_output.put_line("员工号："||r_emp.EMPNO||"员工名："||r_emp.ENAME||"工资："||r_emp.SAL);

        end loop;

end;

select * from emp   

--5：向游标传递一个工种，显现此工种的所有雇员的所有信息(行使参数游标)
declare 

       cursor

       c_job(p_job nvarchar2)

       is 

       select * from emp where JOB=p_job;

       r_job emp%rowtype;

begin 

       for r_job in c_job("CLERK") loop

           dbms_output.put_line("员工号"||r_job.EMPNO||" "||"员工姓名"||r_job.ENAME);

        end loop;

end;

SELECT * FROM EMP



--6：用更新游标来为雇员减佣金：(用if真现,创建一个取emp表一摸一样的emp1表，对emp1表进止点窜操纵),并将更新前后的数据输出出来 

--http://zheng12tian.iteye.com/blog/815770 
        create table emp1 as select * from emp;

        

declare

        cursor

        csr_Update

        is

        select * from  emp1 for update OF SAL;

        empInfo csr_Update%rowtype;

        saleInfo  emp1.SAL%TYPE;

begin

    FOR empInfo IN csr_Update LOOP

      IF empInfo.SAL<1500 THEN

        saleInfo:=empInfo.SAL*1.2;

       elsif empInfo.SAL<2000 THEN

        saleInfo:=empInfo.SAL*1.5;

        elsif empInfo.SAL<3000 THEN

        saleInfo:=empInfo.SAL*2;

      END IF;

      UPDATE emp1 SET SAL=saleInfo WHERE CURRENT OF csr_Update;

     END LOOP;

END;



--7:编写一个PL/SQL法式块，对名字以‘A’或‘S’起头的所有雇员按他们的根基薪水(sal)的10%给他们减薪(对emp1表进止点窜操纵)
declare 

     cursor

      csr_AddSal

     is

      select * from emp1 where ENAME LIKE "A%" OR ENAME LIKE "S%" for update OF SAL;

      r_AddSal csr_AddSal%rowtype;

      saleInfo  emp1.SAL%TYPE;

begin

      for r_AddSal in csr_AddSal loop

          dbms_output.put_line(r_AddSal.ENAME||"正本的工资:"||r_AddSal.SAL);

          saleInfo:=r_AddSal.SAL*1.1;

          UPDATE emp1 SET SAL=saleInfo WHERE CURRENT OF csr_AddSal;

      end loop;

end;

--8：编写一个PL/SQL法式块，对所有的salesman删减佣金(comm)500
declare

      cursor

          csr_AddComm(p_job nvarchar2)

      is

          select * from emp1 where   JOB=p_job FOR UPDATE OF COMM;

      r_AddComm  emp1%rowtype;

      commInfo emp1.comm%type;

begin

    for r_AddComm in csr_AddComm("SALESMAN") LOOP

        commInfo:=r_AddComm.COMM+500;

         UPDATE EMP1 SET COMM=commInfo where CURRENT OF csr_AddComm;

    END LOOP;

END;



--9：编写一个PL/SQL法式块，以晋升2个资历最老的职员为MANAGER（工作岁月越长，资历越老）

--（提示：可以定义一个变量作为计数器把握游标只提取两条数据；也可以在声明游标的时间把雇员中资历最老的两小我查出来放到游标中。）
declare

    cursor crs_testComput

    is

    select * from emp1 order by HIREDATE asc;

    --计数器
    top_two number:=2;

    r_testComput crs_testComput%rowtype;

begin

    open crs_testComput;

       FETCH crs_testComput INTO r_testComput;

          while top_two>0 loop

             dbms_output.put_line("员工姓名："||r_testComput.ENAME||" 工作岁月："||r_testComput.HIREDATE);

             --计速器减一
             top_two:=top_two-1;

             FETCH crs_testComput INTO r_testComput;

           end loop;

     close crs_testComput;

end;

    



--10：编写一个PL/SQL法式块，对所有雇员按他们的根基薪水(sal)的20%为他们减薪，

--假设删减的薪水年夜于300就勾销减薪(对emp1表进止点窜操纵，并将更新前后的数据输出出来) 
declare

    cursor

        crs_UpadateSal

    is

        select * from emp1 for update of SAL;

        r_UpdateSal crs_UpadateSal%rowtype;

        salAdd emp1.sal%type;

        salInfo emp1.sal%type;

begin

        for r_UpdateSal in crs_UpadateSal loop

           salAdd:= r_UpdateSal.SAL*0.2;

           if salAdd>300 then

             salInfo:=r_UpdateSal.SAL;

              dbms_output.put_line(r_UpdateSal.ENAME||":  减薪得败。"||"薪水保持在："||r_UpdateSal.SAL);

             else 

              salInfo:=r_UpdateSal.SAL+salAdd;

              dbms_output.put_line(r_UpdateSal.ENAME||":  减薪告成."||"薪水变为："||salInfo);

           end if;

           update emp1 set SAL=salInfo where current of crs_UpadateSal;

        end loop;

end;

     

--11:将每位员工工作了几年零几月零几天输出出来   

--近似
  --CEIL(n)函数：取年夜于便是数值n的最小整数
  --FLOOR(n)函数：取小于便是数值n的最年夜整数
  --truc的用法 http://publish.it168.com/2005/1028/20051028034101.shtml
declare

  cursor

   crs_WorkDay

   is

   select ENAME,HIREDATE, trunc(months_between(sysdate, hiredate) / 12) AS SPANDYEARS,

       trunc(mod(months_between(sysdate, hiredate), 12)) AS months,

       trunc(mod(mod(sysdate - hiredate, 365), 12)) as days

   from emp1;

  r_WorkDay crs_WorkDay%rowtype;

begin

    for   r_WorkDay in crs_WorkDay loop

    dbms_output.put_line(r_WorkDay.ENAME||"已工作了"||r_WorkDay.SPANDYEARS||"年,零"||r_WorkDay.months||"月,零"||r_WorkDay.days||"天");

    end loop;

end;

  

--12:输进部份编号，按照以下减薪比例施止(用CASE真现，创建一个emp1表，点窜emp1表的数据),并将更新前后的数据输出出来

--  deptno  raise(%)

--  10      5%

--  20      10%

--  30      15%

--  40      20%

--  减薪比例以现有的sal为标准

--CASE expr WHEN comparison_expr THEN return_expr

--[, WHEN comparison_expr THEN return_expr]... [ELSE else_expr] END
declare

     cursor

         crs_caseTest

          is

          select * from emp1 for update of SAL;

          r_caseTest crs_caseTest%rowtype;

          salInfo emp1.sal%type;

     begin

         for r_caseTest in crs_caseTest loop

         case 

           when r_caseTest.DEPNO=10

           THEN salInfo:=r_caseTest.SAL*1.05;

           when r_caseTest.DEPNO=20

           THEN salInfo:=r_caseTest.SAL*1.1;

           when r_caseTest.DEPNO=30

           THEN salInfo:=r_caseTest.SAL*1.15;

            when r_caseTest.DEPNO=40

           THEN salInfo:=r_caseTest.SAL*1.2;

         end case;

          update emp1 set SAL=salInfo where current of crs_caseTest;

        end loop;

end;



--13:对每位员工的薪水进止断定，假设该员工薪水下于其所在部份的均匀薪水，则将其薪水减50元，输出更新前后的薪水，员工姓名，所在部份编号。

--AVG([distinct|all] expr) over (analytic_clause)

---作用：

--按照analytic_clause中的规定礼貌求分组均匀值。
  --阐收函数语法:
  --FUNCTION_NAME(,...)
  --OVER
  --()
     --PARTITION子句
     --按照表达式分区(就是分组),假设省略了分区子句,则全数的成果集被看作是一个单一的组
     select * from emp1

DECLARE

     CURSOR 

     crs_testAvg

     IS

     select EMPNO,ENAME,JOB,SAL,DEPNO,AVG(SAL) OVER (PARTITION BY DEPNO ) AS DEP_AVG

     FROM EMP1 for update of SAL;

     r_testAvg crs_testAvg%rowtype;

     salInfo emp1.sal%type;

     begin

     for r_testAvg in crs_testAvg loop

     if r_testAvg.SAL>r_testAvg.DEP_AVG then

     salInfo:=r_testAvg.SAL-50;

     end if;

     update emp1 set SAL=salInfo where current of crs_testAvg;

     end loop;

end;