Oracle笔记 八、PL/SQL跳转/判断/循环语句块

--goto跳转语句

--在goto 后，跳转到相应的语句，然后执行该语句和后面所有语句

begin

     dbms_output.put_line(‘goto开始了‘);

     goto c;

          --不被执行

          dbms_output.put_line(‘goto‘);

          dbms_output.put_line(‘goto‘);

          dbms_output.put_line(‘goto‘);

          dbms_output.put_line(‘goto‘);

    <<a>>

           dbms_output.put_line(‘goto aaa‘);           

    <<b>>

           dbms_output.put_line(‘goto bbb‘);

    <<c>>

           dbms_output.put_line(‘goto ccc‘);

end;   

--PL/SQL中的sql和rowcount属性：sql代表最近执行的sql语句，rowcount代表最近执行的sql语句影响的行数

declare

  vCount number;

  vDeptno dept2.deptno%type := 10;

begin

  --select count(*) into vCount from dept2;

  --update dept2 set dname = dname || ‘~.~‘ where deptno = vDeptno;

  --delete from dept2 where deptno = 40;

  insert into dept2 select * from dept;

  dbms_output.put_line(‘count:‘ || vCount);

  dbms_output.put_line(sql%rowcount || ‘行受影响‘);

end;

--PL/SQL执行sql语句

begin

  execute immediate ‘create table temp as select * from dept‘;

end;

--动态sql，把sql语句放到变量中并传递参数

declare

     sqlstr varchar2(100);

begin

     sqlstr := ‘insert into scott.dept values(12, :1, :abc)‘;

     --变量是按照占位符顺序插入的

     execute immediate sqlstr using ‘教务部‘, ‘武汉‘;

end;

select * from scott.dept;

--动态sql,把查询结果赋值给变量

declare

       dept_row_data scott.dept%rowtype;

       sqlstr varchar2(100);

begin

     sqlstr := ‘select * from scott.dept where deptno = 11‘;

     execute immediate sqlstr into dept_row_data;

     dbms_output.put_line(dept_row_data.deptno);

end;

--if 语句

--select * from emp;

declare

     vSal emp.sal%type;

begin

  select sal into vSal from emp where empno = 7566;

  if (vSal < 1200) then

    dbms_output.put_line(‘小于1200‘);

  elsif (vSal < 2000) then

    dbms_output.put_line(‘小于2000‘);

  else

    dbms_output.put_line(‘大于2000‘);

  end if;

end;  

--loop循环

declare

  i binary_integer := 10;

begin

  loop

    dbms_output.put_line(i);

    i := i - 1;

    exit when(i < 1);

  end loop;

end;

--while循环

declare

  i binary_integer := 1;

begin

  while i < 11 loop

     dbms_output.put_line(i);

     i := i + 1;

  end loop;

end;

--for 循环

begin

  for i in 1..10 loop

    dbms_output.put_line(i);

  end loop;

  for i in reverse 1..10 loop

    dbms_output.put_line(i);

  end loop;

end;