Database Administration

Lecture 1

Who is DBA??

• DBA is a resource that supervises both the database and the use of the DBMS.

• DBA is usually a group, but sometimes it refers to the database administrator.

What is DBA

• Database administration refers to the whole set of activities performed by a database administrator to ensure that a database is always available as needed. Other closely related tasks and roles are database security, database monitoring and troubleshooting, and planning for future growth.

• Database administration is an important function in any organization that is dependent on one or more databases.

Role of DBA

• The primary role of database administration is to ensure maximum up time for the database so that it is always available when needed. This will typically involve proactive periodic monitoring and troubleshooting. This in turn entails some technical skills on the part of the DBA. In addition to in-depth knowledge of the database in question, the DBA will also need knowledge and perhaps training in the platform (database engine and operating system) on which the database runs.

• A DBA is typically also responsible for other secondary, but still critically important, tasks and roles. Some of these include:

• Database Security: Ensuring that only authorized users have access to the database and fortifying it against any external, unauthorized access.

• Database Tuning: Tweaking any of several parameters to optimize performance, such as server memory allocation, file fragmentation and disk usage.

• Backup and Recovery: It is a DBA's role to ensure that the database has adequate backup and recovery procedures in place to recover from any accidental or deliberate loss of data.

• Producing Reports from Queries: DBAs are frequently called upon to generate reports by writing queries, which are then run against the database.

Policy Formulation and Implementation

• Access Privileges– Users should access the database only in ways in

which they are entitled.• Security– Access restrictions ensure that the database is

secure.– Passwords, encryption, and views implement

security.– Effective password protection is critical.

Planning for Disaster

• Databases can be harmed from hardware and software malfunctions, and outsides forces like floods and power outages.

• DBA’s must take active role in formulating disaster recovery plans.

Archives

• An archive is a place where corporate data is kept.• Information in an archive is removed from the

database and stored in the archive for future reference.

• Archives are usually kept in a mass-storage device like a disk, tape, CD, or a DVD.

• It is important such archives be kept off-site to allow recovery should disaster strike

Data Dictionary Management

• Essentially the catalog, but it contains a wider range of information, including information on tables, fields, indexes, and programs.

• The DBA manages and updates the data dictionary, which establishes naming conventions for tables, fields, etc., and data integrity rules.

Additional responsibilities of DBA

• Training– DBA gives training on the DBMS and how to access

the database• DBMS Support– The DBA is charged with all aspects of a DBMS,

including selection and management– DBA must evaluate each prospective DBMS using a

checklist like that shown inFigure 8.10.

Additional Responsibilities of DBA

• Database design– DBA is responsible for tuning the design, i.e.,

making changes that improve system performance.

Is DBA job Easy ???

• You can find no more challenging job then job of DBA in IT industry. Life of DBA is quite hectic.

• The DBA maintains production and test environments, monitors active application development projects, attends strategy and design meetings, selects and evaluates new products, and connects legacy systems to the Web. And, of course: Joe in Accounting, he just resubmitted that query from hell that’s bringing the system to a halt. Can you do something about that? All of this can occur within a single workday.

• DBAs are expected to know everything about everything. From technical and business jargon to the latest management and technology fads, the DBA is expected to be “in the know.” And do not expect any private time: A DBA must be prepared for interruptions at any time to answer any type of question—and not just about databases, either.

• When application problems occur, the database environment is frequently the first thing blamed. The database is “guilty until proven innocent.” A DBA is rarely approached with a question like “I’ve got some really bad SQL here. Can you help me fix it?” Instead, the DBA is forced to investigate problems where the underlying assumption is that the DBMS or perhaps the DBA is at fault, when the most common cause of relational performance problems is inefficiently coded applications.

Salary of DBA

Source : http://www.indeed.com/salary/Oracle-Database-Administrator.html