how to start an Oracle Database and em console (10g)

Starting an Oracle Database and EM console (10g)

login/su as the user who installed the oracle software (i.e. oracle)
wins: [bash]set ORACLE_SID=sid_name  #the name SID given when creating database[/bash]
linx: [bash]export ORACLE_SID=sid_name
sqlplus /nolog #just log onto the sqlplus console
connect user/passw as sysdba #log-in as a sysdba with user | default: system/manager
#output: Connected to an idle instance. (within SQL console)
startup #to startup the DB
exit #to commit, disconnect and log-off from db-console
lsnrctl status #to show the status of the listener ( may need ./lsnrctl)
lsnrctl start #to start the listener, based on the SID set above
#output: The command completed successfully
emctl start dbconsole #to start the Oracle Enterprise Manager console (web)
#output: ….started.[/bash]


  • listener.ora //the file that has the connection info for DBs
    path: /u01/app/oracle/product/11.2.0/db_1/network/admin/listener.ora
    (or wherever the oracle DB product was installed)

Problems initializing:

  • Shutdown and restart both database(sqlplus) and listener(linx shell)
  • Try deleting and re-creating the database again (if this is a newly created db with no data, else BACK-IT-UP first!!!)


how to enable output in Oracle SQL Developer

To enable output to console window in Oracle SQL Developer (as of

  1. From the menu go to: View > Dbms Output
  2. From the new window (popped-up in the log area) click on the plus sign to enable output
  3. Enter the output you want i.e.:
    [sql]DBMS_OUTPUT.PUT_LINE(‘CLA_CLA_ID: ‘ || V_ASY_CLA_ID2 || ‘, ‘ ||V_ASY_SURNAME2);[/sql]
  4. This should display when SQL code is run

how to check the environment vars -linux

To check environment vars in a linux setup:


…this should return a list of the environment entries and can retrieve entries like:

[bash]HOME # the active user’s home dir
HOSTNAME # the server’s name
ORACLE_HOME # the default path of an oracle installation
ORACLE_SID # the service/name of a db instance[/bash]

how to check if listener working from linux

When checking if a listener is active or not in Oracle:

lsnrctl status

This command should return something similar to the following. Check-out the Services summary:

Services Summary…
Service “PLSExtProc” has 1 instance(s).
Instance “PLSExtProc”, status UNKNOWN, has 1 handler(s) for this service…
Service “” has 1 instance(s).
Instance “dmcl”, status READY, has 3 handler(s) for this service…