范例：
仅启动 SQL*Plus 不登录到数据库
$ sqlplus /nolog
以默认管理员登陆
$ sqlplus / as sysdba
以数据库账户登录
$ sqlplus
$ sqlplus username
$ sqlplus username@sid
$ sqlplus username@//host/sid
$ sqlplus username@//host:port/sid
$ sqlplus username/password
$ sqlplus username/password@sid
$ sqlplus username/password@//host/sid
$ sqlplus username/password@//host:port/sid
$ sqlplus username as sysdba
$ sqlplus username@sid as sysdba
$ sqlplus username@//host/sid as sysdba
$ sqlplus username@//host:port/sid as sysdba
$ sqlplus username/password as sysdba
$ sqlplus username/password@sid as sysdba
$ sqlplus username/password@//host/sid as sysdba
$ sqlplus username/password@//host:port/sid as sysdba
登录数据库并执行 SQL*Plus 脚本文件
$ sqlplus username/password@sid @/home/oracle/createdb
$ sqlplus username/password@sid @/home/oracle/createdb.sql
$ sqlplus username/password@sid @/home/oracle/createdb.sql 10 10 30 40