oracle分页语句和随机取N条记录

分页语句：

使用rownum

SELECT *  FROM (SELECT T.*, ROWNUM RN FROM EMP T WHERE ROWNUM <= 5) WHERE RN >= 3;

SELECT *  FROM (SELECT T.*, ROWNUM RN FROM EMP T) A WHERE A.RN BETWEEN 3 AND 5;

使用rowid

SELECT *  FROM EMP WHERE ROWID IN (SELECT RD                   FROM (SELECT ROWID AS RD, ROWNUM AS RN FROM EMP)                  WHERE RN >= 3                    AND RN <= 5);

随机取N条记录：

SELECT *  FROM (SELECT * FROM EMP ORDER BY DBMS_RANDOM.RANDOM) WHERE ROWNUM <= N;