多项选择题 WhichtwostatementsregardingthecontrolfileandRecoverManageraretrue？（）

单项选择题 You want to drop the TBS1 tablespace from your database.  You also want to delete the corresponding data files automatically， and not have to do it manually.  What should you do？（）

多项选择题 Examine the statement：   SQL> CREATE TABLESPACE user_data  2> EXTENT MANAGEMENT LOCAL  3> SEGMENT SPACE MANAGEMENT AUTO；   Which twp assumptions must be true for this statement to execute successfully？（）