1. Data and Database Administration
Chapter 12
Modern Database Management

2. Outline
Introduction
Traditional Approaches to data & DB administration
Effective data and DB administration functions
Data security
Data Recovery and Backup

3. Introduction
Data are corporate asset just like personnel, physical & financial resources.
Effective data administration provides support for managerial decision making at all levels in the organization.
Ineffective data administration leads to poor data utilization.

4. Data & Database Administration
Data Administration
includes overall management of data resources in an organization, including maintaining corporate-wide definitions and standards.
Database Administration
includes physical database design and dealing with technical issues associated with databases, such as security enforcement, database performance, and backup & recovery.

5. Traditional Data Administration
The data administrator (DA) must be senior-level manager.
He/she should have both technical and managerial skills.
Traditional DA functions:
Database planning, analysis, design, implementation, maintenance & protection.
Establishing procedures for improving database performance.
Providing education, training and consulting support to users.
Resolve disputes that my arise when data are centralized & shared among users.

6. Traditional Database Administration
The database administrator (DBA) carries through the standards and procedures established by the data administrator.
DBA can sometimes take up the role of data administrator too.
The DBA needs to have a variety job skills. He/she should:
Have broad technical background including sound understanding of current H/W architectures.
Have solid understanding of data processing.
Have understanding of database development cycle

7. Traditional Database Administration (contd.)
Have strong design and modeling skills (at conceptual, logical and physical levels).
Have managerial skills to deal with other info system personnel as the database is analyzed, designed & implemented.
Provide support for end users involved with database design and use

8. Evolving Approaches to Data and Database Administration
There are no universally accepted data and database administration structures.
Organizations vary widely in their approaches.
As business practices change, the roles are also changing. However, there is a core set of data and database administration functions that must be met in every organization.
These can be termed as effective data and database administration functions.

9. Effective Data and Database Administration Functions
Data policies, procedures and standards*
Data policies are statements that make explicit the goals of data administration, e.g., “every user must have a password”
Data procedures are written outlines of actions to be taken in order to perform a certain activity, e.g., backup & recovery procedures.
Data standards are explicit conventions and behaviours that are to be followed and that can be used to evaluate DB quality, e.g., naming conventions for DB objects
Planning
involves understanding of organization’s information needs and contribution in development of information architecture.
Example taken from Database Design, Development and Implementation (Rob, Coronel)
Policies
All users must have passwords.
Passwords must be changed every six months.
Standards
A password must have a minimum of five characters.
A password may have a maximum of 12 characters.
Social Security numbers, names, and birth dates cannot be used as passwords.
Procedures
To create a password:
1. The end user sends a written request for an account creation to the DBA.
2. The DBA approves the request and forwards it to the computer operator.
3. The computer operator creates the account, assigns a temporary password, and sends the account
information to the end user. A copy of the account information is sent to the DBA.
4. The user changes the temporary password to a permanent one.
* See slide notes for detail

10. Effective Data and Database Administration Functions (contd.)
Data conflict resolution
In a shared data environment, data & database administrators resolve data conflicts and ownership issues.
Internal marketing
Involves enforcing procedures and policies within the organization to avoid data related problems.
Managing the information repository
Information repositories contain metadata and are replacing data dictionaries in many organizations.
Info repositories are used throughout the DB system life cycle and serve the following*: Users, Automated CASE Tools, Applications, DBMS *
Users - must understand data definitions, business rules & relationships among data objects
Automated CASE Tools - are used to specify & develop info systems
Applications - access and manipulate data in DBs
DBMS - maintain repository & update system privileges, passwords, object definitions, etc.
* See slide notes for detail

11. Effective Data and Database Administration Functions (contd.)
Selection of hardware and software
New hardware and software are being developed at a rapid pace.
The data and database administrators are expected to know about hardware/software architectures to be able to administer both in-house-developed and off-the-shelf application.
Installing and upgrading the DBMS
After selecting a DBMS, performance benchmarking must be conducted before installation.
After installation, periodic update packages (released from vendors) should be used for regular DBMS upgrades.
Tuning database performance
DBs are dynamic, the initial DB design may be required to change with time to meet new requirements. Hence, databases must be rebuilt, reorganized and reindexed to achieve required performance.

12. Effective Data and Database Administration Functions (contd.)
Improving database query processing
Workload against a database expands over time with increase in data and number of users.
DBA must tune DB for performance and improve query processing time.
Managing data security, privacy &integrity
The above must be managed by the database administrators.
Data backup and recovery
DBA must ensure that backup procedures are established and will allow recovery of necessary data in case of losses through
application failure,
hardware failure,
physical or electrical disaster,
human error or malfeasance.

13. Evolving Approaches to Data Administration
Many organizations now have blended the data administration and DB administration roles together. They emphasize the capability to build a database quickly, tuning it for max performance and being able to restore it to production quickly when problems develop.
Quinlan has suggested changes in data and DB administration practices that can be made at each stage of database development life cycle (pg 452,453)
The DBA role will continue to evolve. This role is expected to become more specialized, e.g., distributed DB/network capacity planning DBAs, server programming DBAs, data warehousing DBAs, etc.

14. Data Security
It is the protection of the data against accidental or intentional loss, destruction or misuse.
Due to distributed databases and data access through internet & intranet, data security has become difficult.
Threats to data security
Threats to data security may be direct threats to databases.
To ensure database security, all parts of the system must be secure, including
the database,
the network,
the operating system,
the building in which the database physically resides and
the personnel who have system access.

15. Data Security (Contd.)
Threats to be addressed in a comprehensive data security plan
Accidental losses, including human error, software and hardware-caused breaches.
Theft and fraud
Loss of privacy or confidentiality
Loss of data integrity
Loss of availability

16. Data Security (Contd.) A comprehensive data security plan will include
establishing administrative policies & procedures, physical protection and data management software protections.
Security features of data management software are:
Views or sub schemas
they are created on one or more base tables
they produce dynamic result tables at the time of request
they restrict user view of database
Domains, assertions, checks and other integrity controls
they limit the values a field can hold,
they limit the actions that can be preformed on data
they are enforced by DBMS during DB querying & updating
Assertions are (business rule) statements that place a constraint
- Action assertion
- Structural assertion

17. Data Security (Contd.) Authorization rules User-defined procedures
they identify users, restrict access to data and user actions (e.g., insert, read, modify, delete) against DB objects
User-defined procedures
They define additional constraints or limitations in using DB
Encryption Procedures
They encode/scramble data
Authentication Schemes
They positively identify a person accessing the DB, examples:
biometric devices that can detect personal characteristics (fingerprints, voice prints, retina, signature)
authentication systems such as Kerberos
Establishing no repudiation by biometrics & messaging
Backup, journaling and check pointing capabilities
They facilitate recovery procedures

18. Database Recovery and Backup
Databases are often damaged or lost because of system problems that may be caused by:
Human error,
Hardware failure,
Incorrect or invalid data,
Program errors,
Viruses,
Network failures,
Conflicting transactions or,
Natural disasters
Mechanisms for restoring a database quickly and accurately after loss or damage are known as Database recovery.

19. Basic Recovery Facilities
A DBMS should provide four basic facilities for backup& recovery of DB
Backup facilities
Provide periodic backup copies of portions of or entire database
Journalizing facilities
Maintain an audit trail of transactions and database changes
Checkpoint facilities
Allow DBMS to periodically suspend all processing and synchronize its files and journals
Recovery Manager
Allow DBMS to restore the DB to a correct condition and restart processing transactions