Tasks of a Database Administrator

The following tasks present a prioritized approach for designing, implementing, and maintaining an Oracle Database:

Task 1: Evaluate the Database Server Hardware

Task 2: Install the Oracle Software

Task 3: Plan the Database

Task 4: Create and Open the Database

Task 5: Back Up the Database

Task 6: Enroll System Users

Task 7: Implement the Database Design

Task 8: Back Up the Fully Functional Database

Task 9: Tune Database Performance

These tasks are discussed in succeeding sections.


Task 1: Evaluate the Database Server Hardware

Evaluate how Oracle and its applications can best use the available computer resources. This evaluation should reveal the following information:
• How many disk drives are available to Oracle and its databases
• How many, if any, dedicated tape drives are available to Oracle and its databases
• How much memory is available to the instances of Oracle you will run (see your system's configuration documentation)

Task 2: Install the Oracle Software

As the database administrator, you install the Oracle database server software and any front-end tools and database applications that access the database. In some distributed processing installations, the database is controlled by a central computer (database server) and the database tools and applications are executed on remote computers (clients). In this case, you must also install the Oracle Net components necessary to connect the remote machines to the computer that executes Oracle.

Task 3: Plan the Database

As the database administrator, you must plan:
• The logical storage structure of the database
• The overall database design
• A backup strategy for the database
It is important to plan how the logical storage structure of the database will affect system performance and various database management operations. For example, before creating any tablespaces for your database, you should know how many datafiles will make up the tablespace, what type of information will be stored in each tablespace, and on which disk drives the datafiles will be physically stored. When planning the overall logical storage of the database structure, take into account the effects that this structure will have when the database is actually created and running. Such considerations include how the logical storage structure database will affect the following:
• The performance of the computer executing Oracle
• The performance of the database during data access operations
• The efficiency of backup and recovery procedures for the database
Plan the relational design of the database objects and the storage characteristics for each of these objects. By planning the relationship between each object and its physical storage before creating it, you can directly affect the performance of the database as a unit. Be sure to plan for the growth of the database.
In distributed database environments, this planning stage is extremely important. The physical location of frequently accessed data dramatically affects application performance.
During the planning stage, develop a backup strategy for the database. You can alter the logical storage structure or design of the database to improve backup efficiency.
It is beyond the scope of this book to discuss relational and distributed database design. If you are not familiar with such design issues, refer to accepted industry-standard documentation.

Task 4: Create and Open the Database

When you complete the database design, you can create the database and open it for normal use. You can create a database at installation time, using the Database Configuration Assistant, or you can supply your own scripts for creating a database.

Task 5: Back Up the Database

After you create the database structure, carry out the backup strategy you planned for the database. Create any additional redo log files, take the first full database backup (online or offline), and schedule future database backups at regular intervals.

Task 6: Enroll System Users

After you back up the database structure, you can enroll the users of the database in accordance with your Oracle license agreement, create appropriate roles for these users, and grant these roles.

Task 7: Implement the Database Design

After you create and start the database, and enroll the system users, you can implement the planned logical structure database by creating all necessary tablespaces. When you complete this, you can create the objects for the database.

Task 8: Back Up the Fully Functional Database

Now that the database is fully implemented, again back up the database. In addition to regularly scheduled backups, you should always back up your database immediately after implementing changes to the database structure.

Task 9: Tune Database Performance

Optimizing the performance of the database is one of your ongoing responsibilities as a DBA. Additionally, Oracle provides a database resource management feature that enables you to control the allocation of resources to various user groups.

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ALAA ALI
OCP DBA 9i

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