SQL Plus user login and connection database

start method

1. Menu start

Find the Oracle directory in the computer start menu, find SQL*Plus in the directory to start

2. Command line startup

Shortcut key win+R, enter sqlplus in the input box

User login

1. Login via local administrator

 sys/pwd as sysdba

Note : pwd can be arbitrary, not necessarily the correct password.
Example:

SQL> conn
请输入用户名:  sys/hum as sysdba
已连接。

2. Login via network user

system/pwd 

Note : The pwd here must be the correct password
Example:

SQL> conn
请输入用户名:  system/hyb2001721
已连接。

Or write the username and password separately:

SQL> conn
请输入用户名:  system
输入口令:
已连接。

Connect to the database

1. Connect to the default database

Open the registry editor, check the HKEY_LOCAL_MACHINE\SOFTWARE\ORACLE\KEY_oracle base directory name, check oracle_sid, the corresponding data is the default database, usually orcl

2. Connect to the specified database

用户名/密码 @SID

Example:

SQL> conn
请输入用户名:  system/hyb2001721 @orcl
已连接。

3. Possible problems

[ORA-12560: TNS:protocol adapter error]

Solution :

• Check if the listener is started normally

• Check whether the oracle database instance service is running normally
  

• Modify the default sid of the registry to the existing oracle database