--select * into A from B
--*代表b表中的所有行的记录，即多条记录

--如果你要获取统计记录(单条记录)，可以如下写：
SQL> set serveroutput on;
SQL> declare
  2         x number(2);
  3  begin
  4       select count(*) into x
  5       from emp
  6       where deptno=30;
  7  
  8       dbms_output.put_line('The number of department 30 employees are :'||x);
  9  end;
 10  /

The number of department 30 employees are :6

PL/SQL procedure successfully completed
-----------------
--如果你想获得多条记录，可以用游标返回多条记录：
SQL> declare
  2         cursor x is
  3         select ename,deptno,job,sal
  4         from emp;
  5  begin
  6       for v_emp in x
  7       loop
  8           dbms_output.put_line(
  9           'ename= '||v_emp.ename||
 10           ', deptno= '||v_emp.deptno||
 11           ', job= '||v_emp.job||
 12           ', sal= '||v_emp.sal
 13           );
 14       end loop;
 15  end;
 16  /

ename= SMITH, deptno= 20, job= CLERK, sal= 800
ename= ALLEN, deptno= 30, job= SALESMAN, sal= 1600
ename= WARD, deptno= 30, job= SALESMAN, sal= 1250
ename= JONES, deptno= 20, job= MANAGER, sal= 2975
ename= MARTIN, deptno= 30, job= SALESMAN, sal= 1250
ename= BLAKE, deptno= 30, job= MANAGER, sal= 2850
ename= CLARK, deptno= 10, job= MANAGER, sal= 2450
ename= SCOTT, deptno= 20, job= ANALYST, sal= 3100
ename= KING, deptno= 10, job= PRESIDENT, sal= 5000
ename= TURNER, deptno= 30, job= SALESMAN, sal= 1500
ename= ADAMS, deptno= 20, job= CLERK, sal= 1100
ename= JAMES, deptno= 30, job= CLERK, sal= 950
ename= FORD, deptno= 20, job= ANALYST, sal= 3000
ename= MILLER, deptno= 10, job= CLERK, sal= 1300