SELECT * FROM t order by id LIMIT 1;

SELECT * FROM t where rownum =1 order by id;

 insert into t(id,date) select sys_guid(),sysdate from dual connect by rownum<=10000;

select * from (select id,name from t) where rownum <![CDATA[<=]]> to_number(num);

SELECT 
 * 
FROM
 (SELECT 
  tb.*,
  @rownum := @rownum + 1 AS rownum 
 FROM
  (SELECT 
   id,
   NAME 
  FROM
   t) tb,
  (SELECT 
   @rownum := 0) r) AS t 
WHERE rownum <= CAST(num AS SIGNED INTEGER) ;