oracle dba的练习 恢复数据 with as去重
http://blog.sina.com.cn/s/articlelist_2120624970_0_1.htmlhttp://blog.csdn.net/fw0124/article/details/6210730恢复数据select * from table as of timestamp to_date('2011-01-19 15:28:00', 'yyyy-mm-dd hh24:mi:ss') SQL> with employee_avg_salary as ( 2 select employee_id, avg(salary) avg_salary from salary 3 group by employee_id) 4 select * from employee_avg_salary t 5 where t.avg_salary>(select avg(avg_salary) from employee_avg_salary) 6 / EMPLOYEE_ID AVG_SALARY ----------- ------------ 1 8500 2 6800