Create user

Create a New User in Oracle 12c

Oracle 12c introduces the CDB/PDB multitenant architecture. Creating regular users directly inside the Container Database (CDB) will throw errors. Common users created within the CDB must use the prefix c## / C##.

Log In

1. Open Windows cmd and launch sqlplus

sqlplus

2. Log into the database using the super‑administrator account

Enter user-name: sys as sysdba
Enter password: 【Enter your sys password set during installation】Code language: JavaScript (javascript)

Login success prompt：Connected to: Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production

Create User

Incorrect Syntax

Goal: create user cat with password 123456
Execute SQL:

CREATE USER cat IDENTIFIED BY 123456;

ORA-65096: invalid common user or role nameCode language: HTTP (http)

Cause of error: You are currently in the CDB root container. Common users are forced to have the c## prefix. The name cat does not follow the naming rules.

Correct Way to Create Common User

Execute SQL:

CREATE USER c##cat IDENTIFIED BY Bm123321;Code language: CSS (css)

Execution result：User created.

Assign User Privileges

Wrong Grant Statement

GRANT CONNECT, RESOURCE, DBA TO cat;

ORA-01917: user or role 'CAT' does not existCode language: JavaScript (javascript)

The username is c##cat. When granting permissions, you must use the exact same username used at creation. Do not shorten it to cat.

Correct Grant Statement

GRANT CONNECT, RESOURCE, DBA TO c##cat;Code language: CSS (css)

Privilege description:

1. CONNECT: basic login and connection permission
2. RESOURCE: common developer role, allows creating tables, indexes and other objects
3. DBA: full database administrator privileges (use in test environments; avoid assigning freely in production)

Verify Login with New User

1. Run exit to close the sys admin session, then reopen sqlplus

SQL> exitCode language: PHP (php)

2. Attempt incorrect login

Enter user-name: cat
Enter password: 123456

Error：ORA-01017: invalid username/password; logon denied

3. Correct login method

Enter user-name: c##cat
Enter password: 123456Code language: CSS (css)

Successfully connected to database.

Create user