Wednesday, September 5, 2007

Using Oracle 10g's Database Configuration Assistant

Using Oracle 10g's Database Configuration Assistant

Learning objective

After completing this topic, you should be able to recognize how to configure database identification, management, password, and storage options using the Database Configuration Assistant.

1. Using the Database Configuration Assistant (DBCA)

The Oracle Database Configuration Assistant (DBCA) is a graphical configuration tool that simplifies the creation of Oracle databases. It provides predefined database types and allows full custom database definition.

You start the DBCA from a terminal window. The command to launch the DBCA is dbca.

You type dbca in the terminal window.

The DBCA launches and displays a Welcome page. You click Next.

The Operations page allows you to specify which operation you wish to perform. You can create or delete a database. You can also change an existing database configuration or manage database templates.

You Select Create a Database, then click Next.

On the Database Templates page, you can create a custom database or select a predefined database template:

  • Custom Database
  • Data Warehouse
  • General Purpose
  • Transaction Processing
Custom Database
The Custom Database template allows you the freedom to specify your own settings and customize your database to the needs of your organization.
Data Warehouse
The Data Warehouse template enables you to bring together data from a number of transactional systems. Users can access and analyze the information it contains.
General Purpose
The General Purpose template creates a database that fulfills a broad range of functions.
Transaction Processing
The Transaction Processing template is suited to an environment in which the database system is required to respond immediately to user requests.

You decide to use a template designed to create a database that encompasses a range of functions.

You select General Purpose and click Next.

The Database Identification page enables you to identify your database. You enter the full name of the database - in this case orcl2 – in the Global Database Name field.

The Oracle System Identifier (SID) field contains the name of an instance that will connect to your database. When you type the Global Database Name, the SID field is filled automatically and you click Next.

Note

If you use Real Application Clusters, multiple instances open the same database, and each instance will have a different SID.

Question

Identify the operations you can perform using the DBCA.

Options:

  1. Create a database
  2. Delete a database
  3. Manage templates
  4. Install Oracle

Answer

You can create and delete databases using the DBCA. It also enables you to manage templates.

Option 1 is correct. This option creates a new database or template.

Option 2 is correct. This operation deletes all the database files.

Option 3 is correct. You can create a template from an existing template or database.

Option 4 is incorrect. The Oracle Universal Installer is provided to install Oracle.

Question

Suppose you want to create and configure a database to store customer data. You've accessed the Database Templates page of the DBCA and want to use the General Purpose template to create your database. You also want to name the database "orcl5".

Which sequence of steps would you use to perform this task?

Options:

  1. You select General Purpose and click Next. Then you enter orcl5 in the Global Database Name field and click Next.
  2. You select General Purpose and click Next.Then you enter orcl5 in the SID field and click Next.

Answer

To create a customer database using the General Purpose template, you select General Purpose and click Next. Then you name the database by entering orcl5 in the Global Database Name field. Finally, you click Next.

The Oracle Enterprise Manager enables you to manage the Oracle environment.

The methods for managing the database are

  • Grid Control
  • Database Control
Grid Control
You use Grid Control to manage your database centrally. To choose this option, Oracle Management Agent must be installed on your server. You click the down-pointing arrow to select the management service you wish to use.
Database Control
You select Database Control to manage your database locally. Enterprise Manager Database Control provides web-based features for monitoring and administering the single-instance or clustered database you are creating.

You need to manage your database locally, so you ensure that Configure the Database with Enterprise Manager and Use Database Control for Database Management are selected. You do not want to enable e-mail notifications or daily backup, so you click Next.

The Database Credentials page displays.

Question

Suppose you are creating a database with the DBCA and have decided to manage it using Enterprise Manager. You want to manage your database locally, but you do not require email notifications or a daily backup.

Which sequence of steps would you use to perform this task?

Options:

  1. You select Configure the Database with Enterprise Manager and click Next.
  2. You select Configure the Database with Enterprise Manager. Then you select Use Grid Control for Database Management and click Next.

Answer

To manage your database using Enterprise Manager, you select Configure the Database with Enterprise Manager. Then, to manage your database locally, you ensure Use Database Control for Database Management is selected and click Next.

2. Password and storage options

On the Database Credentials page, you select the passwords that allow users to access your database.

You can provide separate passwords for each of the administrative users – SYS, SYSTEM, DBSNMP, and SYSMAN. Alternatively, you can provide one password for all of these users.

You decide to use one password for all users, so you accept the default Use the Same Password for All Accounts and type a password in the Password and Confirm Password fields. Then you click Next.

There are three options for types of database storage mechanisms:

  • File System
  • Automatic Storage Management (ASM)
  • Raw Devices
File System
This storage mechanism uses the file system of your operating system to manage files. You can choose to store your files in a specific directory.
Automatic Storage Management (ASM)
Automatic Storage Management simplifies database administration by allowing you to manage disk groups instead of a large number of database files. A disk group is a small set of disk devices that are managed as a single logical unit. You can also use mirroring or striping.
Raw Devices
A raw device is a disk partition that does not have a file system. Choosing this storage mechanism allows you to manage your storage devices outside of your operating system's file system.

Before selecting this option, you need to make sure that the raw devices are configured and identified and that your site has a raw partition for each Oracle data file.

Suppose you want to use your operating system's file system to manage files.

You select the File System storage mechanism and click Next.

The Database File Locations page allows you to choose a directory to store your database files.

Question

Match each file storage mechanism to the situation in which it would be best used.

Options:

  1. Automatic Storage Management (ASM)
  2. File System
  3. Raw Devices

Targets:

  1. You have a large number of database files and need to simplify database administration
  2. You want to manage your storage devices outside of your operating system's file system
  3. You want to use your operating system's file system to manage files

Answer

File System uses the file system of your operating system to manage files. You can manage storage devices outside of your current file system using Raw Devices. ASM uses disk groups to simplify database administration.

ASM allows you to manage disk groups instead of a large number of database files. It simplifies database administration.

The File System option uses the file system of your operating system to manage files. You can choose to store your files in a specific directory.

Raw Devices allows you to manage storage devices outside of your current file system. Your site should have a raw partition for each Oracle data file.

Question

You are using the DBCA to create a database and are currently on the Passwords page. You want to configure the database so that all users use the password pass to gain access. You also want to use your operating system's file system to manage files.

Which sequence of steps would you use to perform this task?

Options:

  1. You select Use the Same Password for All Accounts. Next, you type pass in the Password Field. Then you type pass in the Confirm Password field and click Next. Finally, you select File System and click Next.
  2. You select Use different Passwords. Next, you type pass in the Password field. Then you type pass in the Confirm Password field and click Next. Finally, you select Automatic Storage Management (ASM) and click Next.

Answer

To configure one password for all users, you select Use the Same Password for All Accounts. Next, you type pass in the Password field. Then you type pass in the Confirm Password field and click Next. Finally, to use your operating system's file system to manage files, you select File System and click Next.

Summary

The Oracle Database Configuration Assistant (DBCA) is a graphical tool that provides an easy way to create Oracle databases. It enables you to create or delete a database, change an existing database configuration, or create a template. You use Oracle Enterprise Manager to manage the database.

DBCA allows you to select the passwords that grant access to your database. You can specify either separate passwords for each user, or one password for all. There are three storage mechanisms you can use for the database – File System, Automatic Storage Management , and Raw Devices.

No comments: