ORACLE:SELECT INTO变量在WHERE子句中使用

我可以用 select into 将变量的原始值作为select语句中where子句的一部分?

EI将按预期工作以下代码:

declare
v_id number;
v_table number; --set elsewhere in code to either 1 or 2
begin
  select id into v_id from table_1 where name = 'John Smith';
  if(v_table = 2) then
    select id into v_id from table_2 where fk_id = v_id;
  end if;
end;