plsql – 获取第一行 – 哪一个更好？

LV_id number;
Cursor CR_test Is
  select t.id
  from table1 t
  where t.foo = p_foo
  order by t.creation_date; 

Open CR_test;
Fetch CR_test
 Into LV_id;
Close CR_test;

或者这个：

select x.id
from(select t.id
     from table1 t
     where t.foo=p_foo
     order by t.creation_date) x
where rownum = 1

以上两者都有类似的结果,但我需要知道哪一个更有效！

You should do it in a single SQL statement if at all possible.
If you cannot do it in a single SQL Statement,then do it in PL/SQL.
If you cannot do it in PL/SQL,try a Java Stored Procedure.
If you cannot do it in Java,do it in a C external procedure.
If you cannot do it in a C external routine,you might want to seriously think about why it is you need to do it…

http://tkyte.blogspot.com/2006/10/slow-by-slow.html

（编辑：李大同）

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