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