修改Oracle数据库的最大连接数

(1)用sys登录sqlplus:
#sqlplus / as sysdba
(2) 查看最大连接数： 
sqlplus>select value from V$parameter where name='processes';
(3)查看当前连接数： 
sqlplus>select count (*) from V$process;
(4)把最大连接数改成300：
sqlplus>alter system set processes=300 scope=spfile;
(5)重启数据库:
sqlplus>shutdown immediate;
sqlplus>startup;