oracle数据库的quiesce,unquiesce,suspend,resume

quiesce状态即静默状态，可以用下面的SQL语句使得数据库处于quiesce状态：
alter system quiesce restricted;
quiesce状态下的数据库不能被non-dba用户连接，而dba用户仍然可以进行查询修改操作。
alter system unquiesce
可以将数据库设置成unquiesce状态。
quiesce and unquiesce are the new feature of 10g,they can alter db to restricted state without to shutdown and restart database,and eliminate the time exhaust.

in oracle which version prior to 10g,you can do this through the following command:
1,shutdown;
2,startup restricted;
which can made the db to restricted state,so the dba user can do some particular task.

compare to quiesce state,you can alter db to suspend state(停顿状态)for particular jobs;
the command as following:
alter system suspend.
in suspend state,all you can do is read data from db using dba user,you can't modify or insert data to db.
you can alter db to normal using :
alter system resume;