〖Orz〗求一条sql语句

SELECT * FROM 'phome_ecms_news' WHERE classid = (SELECT classid FROM 'phome_enewsClass' where islast=1 RAND() limit 1) RAND() limit 1;

SELECT * FROM 'phome_ecms_news' WHERE classid IN  
  (
  SELECT classid FROM 'phome_enewsClass' where islast=1 ORDER BY RAND() limit 1
  )
  ORDER BY RAND() limit 1;