oracle分页

//第一种
SELECT * FROM 
(
SELECT A.*, ROWNUM RN 
FROM (SELECT * FROM TABLE_NAME) A 
WHERE ROWNUM <= 40
)
WHERE RN >= 21​

//第二种
SELECT * FROM 
(
SELECT A.*, ROWNUM RN 
FROM (SELECT * FROM TABLE_NAME) A 
)
WHERE RN BETWEEN 21 AND 40

对比结果：