Connect to Database

Use these methods to quickly connect to Oracle DB in various environments.

1. SQL*Plus (EZConnect)

sqlplus username/password@host:port/service_name

Example:

sqlplus hr/hr123@orclhost:1521/ORCLPDB1

2. SQL*Plus (Local as SYSDBA)

sqlplus / as sysdba

Works when you’re logged in as Oracle user on DB server.

3. SQL*Plus via TNS

sqlplus username/password@TNS_ALIAS

📍 Define alias in tnsnames.ora (usually in $ORACLE_HOME/network/admin)

4. RMAN (Backup/Restore)

rman target username/password@host:port/service_name

Or locally:

rman target /

5. SQL Developer (GUI)

Host:        LAPTOP-00001111  
Port:        1521  
Service:     FREE  
Username:    sys  
Password:    ********

6. JDBC (Apps, Java)

jdbc:oracle:thin:@//host:1521/service_name

7. SQLcl (Modern CLI)

sql hr/hr123@host:1521/service_name

8. OEM / PL/SQL Developer (GUI)

OEM: Web login
PL/SQL Developer: TNS or direct settings

📌 Notes:

  • Default port is 1521.
  • Prefer SERVICE_NAME over SID unless explicitly required.
  • Listener must be running: lsnrctl status