# Oracle Database Administration/Instances

This lesson introduces Oracle database instance management.

## Objectives and Skills

Objectives and skills for the instance management portion of Oracle Database Administration I certification include:
* Managing the Oracle Instance
** Setting database initialization parameters
** Describe the stages of database startup and shutdown
** Using alert log and trace files
** Using data dictionary and dynamic performance views

## Readings

* Oracle: Database 2-Day DBA Getting Started with Database Administration

## Multimedia

* YouTube: Oracle Enterprise Manager OEM

## Activities

* Use Oracle Enterprise Manager.
** Complete the tutorial Oracle: Getting Started with Oracle Enterprise Manager.
* Stop and start Enterprise Manager.
** Review Oracle: Administering a Database on Windows.
** Use the following commands to view status, stop, and start the Enterprise Manager console service: emctl status dbconsole emctl stop dbconsole emctl start dbconsole
** Use the Windows Services management console to view status, stop, and start the OracleDBConsoleorcl console service.
** Use the following commands to view status, stop, and start the NET command to stop and start the OracleDBConsoleorcl console service: net start net stop OracleDBConsoleorcl net start OracleDBConsoleorcl
* Test connecting to Enterprise Manager.
** Use emctl, Services, or net to stop Enterprise Manager.
** While the service is stopped, attempt to connect to Enterprise Manager using a web browser. The connection will fail.
** While the service is stopped, attempt to connect to the Oracle database using SQL*PLUS. The connection should succeed.
** Use emctl, Services, or net to start Enterprise Manager.
** Use a web browser to connect to Enterprise Manager to verify the service started.
* User Enterprise Manager Database Control to shutdown and startup the database.
** Review Oracle: Administering a Database on Windows.
** Use Enterprise Manager Database Control to shutdown the database. Under Advanced Options, choose Transactional.
** While the database is shutdown, attempt to connect to the database with SQL*PLUS.
** Use Enterprise Manager to startup the database. Under Advanced Options, view the options available but keep the default settings.
* Use SQL*PLUS to shutdown and startup the database.
** Review Oracle: Administering a Database on Windows.
** Use the following command to shutdown the database: SHUTDOWN TRANSACTIONAL
** Use the following command to startup the database: STARTUP
* Use SQL*PLUS to shutdown and startup the database in stages:
** Review Oracle: Starting Up a Database.
** Use the following command to close and dismount the database: SHUTDOWN IMMEDIATE
** Use the following command to verify instance status: SELECT * FROM V$INSTANCE;
** Use the following command to startup the database: STARTUP NOMOUNT
** Use the following command to verify instance status: SELECT * FROM V$INSTANCE;
** Use the following command to mount the database: ALTER DATABASE MOUNT;
** Use the following command to verify instance status: SELECT * FROM V$INSTANCE;
** Use the following command to open the database: ALTER DATABASE OPEN;
** Use the following command to verify instance status: SELECT * FROM V$INSTANCE;
* View the alert log.
** Review Oracle: Viewing the Alert Log.
** Use Enterprise Manager to view Alert History and Alert Log Contents.
** Use SQL*PLUS to locate the alert log with the following query: SELECT * FROM V$DIAG_INFO;
** Use a text editor to open and view the alert log.
* Use data dictionary and dynamic performance views.
** Review Oracle: Data Dictionary and Dynamic Performance Views.
** Use the following query to identify available DBA_ views: SELECT TABLE_NAME FROM DICTIONARY WHERE TABLE_NAME LIKE 'DBA_%';
** Use the following query to identify available ALL_ views: SELECT TABLE_NAME FROM DICTIONARY WHERE TABLE_NAME LIKE 'ALL_%';
** Use the following query to identify available USER_ views: SELECT TABLE_NAME FROM DICTIONARY WHERE TABLE_NAME LIKE 'USER_%';
** Use the following query to identify available V$ views: SELECT TABLE_NAME FROM DICTIONARY WHERE TABLE_NAME LIKE 'V$%';
** Select records from one or more DBA_, ALL_, USER_, and V$ views.

## Lesson Summary

* Oracle database utilities depend on correct environment variable settings for ORACLE_HOME and ORACLE_SID.
* %ORACLE_HOME%\bin must be included in the PATH environment variable.
* Enterprise Manager Control (emctl) is used to start, stop, and display the status of the Enterprise Manager console website.
* The Enterprise Manager database home page is located at https://server:1158/em.