问题：
在用PL/SQL进行登录时，出现：”ora-01045 :user system lacks create session privilege; logon denied”。
原因：没有权限
在Google找到这段的说明：
What does “ORA-01045: user USERNAME lacks CREATE SESSION privilege;
logon denied” mean?
It means that the username and password with which you tried to login are known and accepted by the oracle server, but that the username doesn’t have permission to create a session. If you think this username should have permission to create sessions send mail to acisdba.
解决方法：
用sys登入Oracle DB后,下grant create session to UserName;(UserName是登录出错的用户名)
