2. What is Database Administration ?
Database administration' is the process of establishing computerized databases, and insuring their recoverability, integrity, security, availability, reliability, and performance.

3. Introduction to Databases
A Database is a collection of a logically related data. And description of this data
A database Management System (DBMS) is the software that manages and controls access to the database.
Ex: Oracle 10g, MS Access, MySql, SQLServer 2007, SqlLight, DB2

4. Examples of database systems
Supermarket products
Purchases, checkout bar code reader, a program accesses the database to obtain item description and price, then updates stock balances
Credit card details
CC reader accesses a database to check the credit present purchases and credit limit. Another program updates balances
Holiday and flight details for travel agents
Booking arrangements, Travel agent invoicing database.
Library database
Books’ details, index, borrowers and borrowing details
Insurance database
University admin and registration database

5. File Based Approach .
The flat-file style of database are ideal for small amounts of data that needs to be human readable or edited by hand. Essentially all they are made up of is a set of strings in one or more files that can be parsed to get the information they store; great for storing simple lists and data values, but can get complicated when you try to replicate more complex data structures.

6. Limitations of the File Based Approach
Separation and isolation of data
An example is a list of course that matches a potential major, since two files have to be accessed: Courses and Major. A program has to be written to create a temporary file that contains the required details
Duplication of data
- Duplication is wasteful: time, money, and storage space
- Duplication leads to loss of data integrity and consistency
Data dependence.
Incompatibility of files
Proliferation (تكاثر، توالد) of application programs
which keeps programmers very busy, and reduce the quality of programs

7. Database Approach
A database is a shared collection of logically related data (and a description of this data) designed to meet the info needs of an org. It is a large repository of data that is a corporate shared resource.
A database is also defined as a self-describing collection of integrated records;

8. The Database Management System (DBMS)
A DBMS is a software system that enables users to define, create, and maintain the database and provides controlled access to it.
A DBMS provides the following facilities: 1) Allow users to define a database through DDL
( Data Definition Language )
Ex: ) Allow user to insert, update, delete, and retrieve data – DML
( Data Manipulation Language)
Ex:
3) Control access to the database, such as security, integrity, concurrency control, recovery control, and user-accessible catalog.
concurrency control: Managing Simultaneous Operation On DB
without having Interleaved.
Ex: Locking

9. Components of the DBMS Environment
Hardware
Software
Data
Procedures
People (Users) (Roles)

10. Roles in the Database Environment DB USERS
Database Administrators (DBA)
Database Designers
Application Programmers
End-Users( Naïve , Sophisticated)

11. 1) Database Administrators (DBA) Responsibilities:
1) Manage Users( Create User , Grant and Revoke Privileges)
2) Defining Security & Integrity Checks
3) Monitoring Performance
4) Defining Backup / Recovery Procedures
5) Setting System Parameters
6) Acquiring Hardware and Software
7) Define DB Procedures , Triggers , …….
2) Database Designers
1) Define DB Schema (Structure , Types , Constraints)
2) Communicate with end user and understand their needs

12.  3) Application Programmers
4) End-Users
They are the clients for the database to serve their information needs.
Naïve users
They do not need to know about the database;
They access the database through simple application programs
such as data entry.
 Sophisticated users
They are familiar with the structure of the database and the functionality of the DBMS.
They use high-level query language, such as SQL.

13. DBA Responsibilities Defining the Schema Liaising with Users
The DBA defines the schema which contains the structure of the data in the application. The DBA determines what data needs to be present in the system ad how this data has to be represented and organized.
Liaising with Users
The DBA needs to interact continuously with the users to understand the data in the system and its use.
Defining Security & Integrity Checks
The DBA finds about the access restrictions to be defined and defines security checks accordingly. Data Integrity checks are also defined by the DBA.

14. DBA Responsibilities (count.)
Defining Backup / Recovery Procedures
The DBA also defines procedures for backup and recovery. Defining backup procedures includes specifying what data is to backed up, the periodicity of taking backups and also the medium and storage place for the backup data.
Monitoring Performance
The DBA has to continuously monitor the performance of the queries and take measures to optimize all the queries in the application.

15. DBA Challenges
- Ever Changing Technologies - Never ending requests - Urgency of a client’s demands for data - Need to maintain a secure, yet available database environment

16. The History of DBMS
Hierarchical Model Network Model first Generation DBMS relational model The extended relational model second Generation DBMS Object Oriented DBMS and Object-Relational DBMS These are called third Generation DBMS

17. Advantages of DBMSs Control of Data Redundancy Data Consistency
Economy of scale
Sharing of data
Improved data integrity
Improved security
Improved Backup and Recovery Services
Increased Productivity
Increased Concurrency
Improved Data Accessibility and Responsiveness

18. Disadvantages
Complexity
Size
Cost

19. Functions of a DBMS Data storage, retrieval, and update
A DBMS must provide users with the ability to store, retrieve, and update data in the database. It should hide the internal physical implementation details from users
A user-accessible catalog
A DBMS must provide a catalog in which descriptions of data items are stored and which is accessible to users.

20. Functions of a DBMS Transaction Support Concurrency Control Services
A DBMS must furnish a mechanism that will ensure that either all updates corresponding to a given transaction are made or that none of them is made. This is to prevent the database being in an inconsistent state. A transaction is a series of actions, carried out by a single user, or a program that access or changes the contents of the database.
Concurrency Control Services
A DBMS must furnish a mechanism to ensure that the database is updated correctly when multiple users are updating the database concurrently

21. Functions of a DBMS Recovery services Support for data communication
A DBMS must furnish a mechanism for recovering the database in the event that the database is damaged in any way.
Security services
A DBMS must furnish a mechanism to ensure that only authorized users can access the database.
Support for data communication
A DBMS must be capable of integrating with communication software.

22. Functions of a DBMS Integrity services
A DBMS must furnish a means to ensure that both the data in the database and changes to the data follow a certain rules.
Services to promote data independence
A DBMS must include facilities to support the independence of programs from the actual structure of the database.
Utility services
A DBMS should provide a set of utility services. These are tools to help the DBA to administer the database effectively, such as import facilities, monitor facilities, statistical analysis programs, index reorganization facilities, and many others.

23. The system Catalog It is called sometime DATA DICTIONARY
The catalog stores data about the data (meta-data)

24. Views and their advantages
A view is a subset of the database, presented to one user or set of users.
The benefits of views are:
They reduce complexity by letting users see the data in the way they want
They provide security by excluding data that some users should not see
They customize the appearance of the database, such as changing attribute names
They hide changes in the database and provide consistent view of the database to users. The also provide the program-data independence mentioned earlier