title: Sqlplus login without password
body: <p>I installed Oracle 11gR2 on my linux server. When I want to login via sys user on my db, I enter "sys as sysdba" and when system give password , I push enter and I can login on my db with sqlplus.</p>
  
  <p>But, when I try to connect on Windows with PL-SQL tool, system wants to password. If I didn't write password (I defined password, password is "sys"), I cannot login on my db.</p>
  
  <p>Why?</p>