从sql * Plus手册
http://download.oracle.com/docs/cd/B19306_01/server.102/b14357/ch8.htm#sthref1597
http://download.oracle.com/docs/cd/B19306_01/server.102/b14357/ch8.htm#sthref1597
SET TERMOUT
SET TERMOUT OFF suppresses the display so that you can spool output from a script without
seeing it on the screen.If both spooling to file and writing to terminal are not required,use SET TERMOUT OFF in >sql scripts to disable terminal output.
SET TERMOUT is not supported in isql*Plus