Check the CBO stats gathering job	Disable the stats gathering job

  1.Check the processes instance parameter value
  The processes instance parameter needs to be set to at least 300.

  2.Check the session_cached_cursors instance parameter value.
  The session_cached_cursors instance parameter should be set to 300.
  Any value between 200 and 500, inclusive, will be accepted.

 3.Check the job_queue_processes instance parameter value.
   The job_queue_processes instance parameter should be set to 20.

 4.Check the shared_pool_size instance parameter value.
   The shared_pool_size instance parameter should be set to
   at least 600 megabytes or roughly one third of the sga_target size.

 5. Check the redo log size.
    The size of the EM database instance should be 300 megabytes or greater.
    Generally, there should be 3 or more redo logs available of this size.

 6. Ensure that the EM tablespace has at least one datafile set to autoextensible
    Add at least one datafile with the autoextend attribute to the EM tablespace

 7.Check the open_cursors instance parameter value.
   The open_cursors instance parameter should be set between 300 and 400, inclusive.

 8.Check the sga_target instance parameter value.
   The sga_target instance parameter should be set to at least 2 gigabytes, and
   roughly twice the size of the pga_aggregate_target setting.

 9.Check for invalid objects in the EM repository
   Compile all invalid objects in the EM repository

==> 如果之前你的db 安装了EM 的话，那么这条命令可以帮助你：