Oracle database using SQL PLUS simple usage

Oracle database using SQL PLUS user login system
1. Common system users:

• sys
• system
• sysman
  Note:
• The three password is usually set when you install your database password
• sys permissions greater than the system authority

2. Open SQL Plus:
Enter the user name and password in the format:
<username>[/<password>][@<connect_identifier>]
eg: system/123456
success appears to connect to:

login successful

So then log on sys? Log how it
connect sys/123456 as sysdba;
successfully displays Connected:

success

3. Check the login user:
show user
You can also use the data dictionary dba_users
data dictionary table in the database is provided for viewing database information
input desc dba_usersdisplay information on this table
as we want to see users, enter again: select username from dba_users;
Note: Be sure to add ";" number!