In one of your online transaction processing （OLTP） applications， most users frequently modify the values， including the key values， of the application tables. Some users generate application reports by using multiple application tables. 
What is the best table structure that you can use to gain optimal performance？（）

In your test database， you have created the ORDERS table as an index-organized table （IOT）. To facilitate faster querying， you have created a mapping table and a bitmap index on the ORDER_FILLED column. You observe that the query performance degrades when users perform a large volume of transactions. 
While investigating the reason， you find that the mapping table segment is fragmented， leading to poor performance.  
Which option would you use to defragment the mapping table without affecting the original table data？（）