Oracle流程控制语句

if...else

set serverout on;
declare n number:=1;
        v varchar2(20):='world';
begin
   dbms_output.put_line('hello'||n||v);
end;


set serverout on;
declare emp_count number;
begin
  select count(*) into emp_count from emp where sal>=3000;
  if emp_count>0 then
    dbms_output.put_line('有'||emp_count||'个员工的基本薪资大于等于3000');
  else
    dbms_output.put_line('没有员工的基本薪资大于等于3000'); 
  end if;
end;


set serverout on;
declare emp_count number;
begin
  select count(*) into emp_count from emp where sal>=3000;
  if emp_count=1 then
    dbms_output.put_line('有1个员工的基本薪资大于等于3000');
  else if emp_count>1 then
    dbms_output.put_line('有超过1个员工的基本薪资大于等于3000');
  else
    dbms_output.put_line('没有员工的基本薪资大于等于3000'); 
  end if;
  end if;
end;

case...when

set serverout on;
declare emp_count number;
begin
  se