Responsibilities of Oracle DBA

If you want to become an oracle DBA, you should first understand what an Oracle DBA’s jobs is. The basic roles of the DBA are fairly consistent among different companies, but these duties might be expanded based on the size of the company and the experiences, of the DBA. In fact, the DBA is considered the main resource for DBMS experience and knowledge in many companies.

Let’s look at these roles and responsibilities and determine what skills are necessary to fulfill these duties. Here the roles and responsibilities are divided into two categories: basic duties and additional duties. The dividing line between these is not clear; there is significant overlap.

Basic Duties of the DBA

Here are some of the basic roles of the Oracle DBA. This is not an all-inclusive list. Depending on your installation and stall, your duties might not include all of these, or might include many more items. This section in simply intended as a general guide.

1)Installation of new software:

It is primarily the job of the DBA to install new versions of Oracle software, application software, and other software related to DBMS administration. It is important that the DBA or other IS staff ,members test this new software before it moved into a production environment.

2)Configuration of hardware/software administrator:

To many cases the system software can only be accessed by the system administrator. In this case, the DBA must work closely with the system administrator to perform software installations, and to configure with DBMS.

3)Security administration:

One of the main duties of the DBA is on monitor and administer DBMS security. This involves adding and removing users, administering quotas, auditing, and checking for security problems.

4)Performance Tuning and Monitoring:

The DBA must continually monitor system performance and be prepared to retune the system as necessary. Even a well-tuned system must be constantly monitored and adjusted. Sometimes this involves changing tuning parameters, other times this involves rebuilding an index or restructuring a table.

5)Backup and recovery:

Perhaps the most important responsibility of the DBA is effective the data in the system. To effectively do this, you must develop an effective backup and recovery strategy and make sure it is carried out. A DBA’s chief responsibility is to maintain the integrity of the database. It is important that the backup and recovery process be periodically tested.

6)Routine scheduled maintenance:

It is the job of the DBA to schedule routine DBMS maintenance and early out this maintenance and carry out this maintenance. This maintenance is regularly carried out in the early hours of the morning or on weekends when this maintenance causes the least inconvenience to the user community.

Additional Duties of the DBA

Some of the more advanced duties of the Oracle DBA might include the following:

1)Data analysis:

The DBA will frequently be called on to analyze the data stored in the database and to make recommendation relating to performance and efficiency of that data storage. This might relate to the more effective use of indexes or the use of some feature such as the Parallel Query option.

2)Database design:

The DBA is often involved at the preliminary database-design stages. Through the involvement of the DBA, many problems that might can be eliminated. The DBA knows the DBMS and system, can point out potential problems, and can help the development team with special performance considerations.

3)Data modeling and optimization:

By modeling the data, it is possible to optimize the system layout to make the most advantage of your I/O subsystem.

4)Assisting developers with SQL and stored procedure development:

The DBA should be prepared to be a resource for developers and users. The DBA is often called on to help with SQL problems as well as to design and write stored procedures.

5)Enterprise standards and naming conventions:

Because many different groups might perform different roles in developing and deploying applications, it is often the DBA who is called on to help define enterprise standards and naming conventions as well as to ensure that new application are conforming to these standards.

6)Development of production migration procedures:

Because the DBA is responsible for the availability and reliability of the DBMS and application using that DBMS, it is up to the DBA to develop and maintain procedures for rolling out new applications and DBMS software. This involves evaluating new software or patches as well as testing them. It is up to the DBA to guarantee the stability and robustness of the system.

7)Evaluation of new software:

The DBA might be called on to evaluated new software and make recommendations based on that evaluation. This might be related to a software purchase rollout of new version of software. This evaluation must be done in the context of the stability of the system. It is your responsibility to maintain system stability and reliability.

Brief History of Oracle

In 1977, Larry Elliso, Bob Minner, and Ed Oates formed a company called Relation Software Incorporated (RSI). This company built an RDBMS called Oracle. Ellison,, Minner, and Otates made a key decision: to develop their RDBMS using C and SQL interface. Soon after, they came out with version 1, a prototype.

In 1979, RSI delivered its first product to customers. The Oracle RDBMS version 2 worked on the Digital PDP-11 running the RSX-11 operating system and was soon ported to the DEM VAX system.

1983 heralded the release of version 3, which touted changes in the SQL language as well as performance enhancements and other improvements. Unlike earlier versions, version 3 was written almost entirely in C. At this point, RSI changed its name to Oracle Corporation.

Oracle version was released in 1984. This version supported both the VAX system and the IBM VM operating system. Version 4 was the first version to incorporate read consistency version 5, introduced in 1985, was a milestone because it introduced client/server computing to the marker with the use of SQL*net. Version 5 was also the first MS-DOS product to break through the 640KB barrier.

In 1988, Oracle presented version 6, which introduced low-level locking as well as a variety of performance improvements and functionality enhancements, including sequence generation and deferred writes. I was introduced to Oracle was days when we even variety of different platforms and operating systems.

In 1991, Oracle introduced the Oracle Parallel Server option on version 6.1 of the Oracle RDBMS on the DEC VAX platform. Soon the Parallel Server option was available on a variety of platforms.

Oracle7, released in 1992, included many architectural changes in the area of memory, CPU, and I/O utilization. Oracle7 is the full-featured RDBMS to which you are accustomed, the one you’ve been using for many years. Oracle7 introduced many advance in the area of ease of use, such as the SQL*DBA tools and database roles.
Finally, in 1997 Oracle introduced Oracle8, which added object extensions as a host of new features and administrative tools.

For more information about the history of Oracle(specifically about the Oracle server), check out the two-part article by Ken Jacobs in the January(February and March/April 1995 issues of Oracle Magazine.

For more information about the Oracle corporation, its products, and about working with Oracle, check out.oracle.com. This Web site contains a wealth of information about Oracle parterships and products as well as information about Oracle Developer Program, which specifically assists developers.

What Affects Oracle Performance?

Because one of the roles of the DBA is to anticipate, find, and fix performance problems, you must know what types of things affect performance. To understand why these things affect performance, you must first review the basics of how a computer system works.

This is the main part that affecting your Computer:

Overview of Computer Architecture

Your computer system consists of thousands of individual components that work in harmony to process data. Each of these components has its own job to perform, and each has its own performance characteristics.

The brainpower of the system is the Central Processing Unit(CPU), which processes all the calculations and instructions that run on the computer. The job of the rest of the system is to keep the CPU busy with instructions to process. A well-tuned system runs at maximum performance if the CPU or CPU are busy 100% of the time.

So how does the system keep the CPUs busy? In general, the system consists of different layers, or tiers, of progressively slower components. Because faster components are typically the most expensive, you must perform a balancing act between speed and cost efficiency.

CPU and Cache

The CPU and the CPU’s cache are the fastest components of the system. The cache is high-speed memory used to store recently used data instructions so that it can provide quick access if this data is used again in a short time. Most CPU hardware designs have a cache built into the CPU chip. This internal cache is known as a Level 1 (or L1) cache. Typically, an L1 cache is quite small-8-16KB.

When a certain piece of data is wanted, the hardware looks first in the L1 cache. If the data is there, it’s processed immediately. If the data is not available in the cache, the hardware looks in the L2 cache, which is external to the CPU chip but located close to it. The L2 cache is connected to the CPU chip(s) on the same side of the memory bus as the CPU. To get to main memory, you must use the memory bus, which affects the speed of the memory access

CPU Design

Most instructions processing occurs in the CPU. Although certain intelligent devices, such as disk controllers, cam process some instruction, the instructions these devices can handle are limited to the control of dada moving to and from the devices. The CPU works from the determine how quickly these instructions are executed.

The CPU usually falls into one of two groups process:

Complex Instructions Set Computer(CISC)or
Reduced Instructions Set Computer(RISC).

Overview of Computer Architecture

Your computer system consists of thousands of individual components that work in harmony to process data. Each of these components has its own job to perform, and each has its own performance characteristics.

The brainpower of the system is the Central Processing Unit(CPU), which processes all the calculations and instructions that run on the computer. The job of the rest of the system is to keep the CPU busy with instructions to process. A well-tuned system runs at maximum performance if the CPU or CPU are busy 100% of the time.

So how does the system keep the CPUs busy? In general, the system consists of different layers, or tiers, of progressively slower components. Because faster components are typically the most expensive, you must perform a balancing act between speed and cost efficiency.

CPU and Cache

The CPU and the CPU’s cache are the fastest components of the system. The cache is high-speed memory used to store recently used data instructions so that it can provide quick access if this data is used again in a short time. Most CPU hardware designs have a cache built into the CPU chip. This internal cache is known as a Level 1 (or L1) cache. Typically, an L1 cache is quite small-8-16KB.

When a certain piece of data is wanted, the hardware looks first in the L1 cache. If the data is there, it’s processed immediately. If the data is not available in the cache, the hardware looks in the L2 cache, which is external to the CPU chip but located close to it. The L2 cache is connected to the CPU chip(s) on the same side of the memory bus as the CPU. To get to main memory, you must use the memory bus, which affects the speed of the memory access

CPU Design

Most instructions processing occurs in the CPU. Although certain intelligent devices, such as disk controllers, cam process some instruction, the instructions these devices can handle are limited to the control of dada moving to and from the devices. The CPU works from the determine how quickly these instructions are executed.
The CPU usually falls into one of two groups process:

Complex Instructions Set Computer(CISC) or
Reduced Instructions Set Computer(RISC).