pert 1 sistem basis data

THX TO STOPIRA

1. Describe each of the following terms;
1. Data

Data adalah catatan atas kumpulan fakta. Data merupakan bentuk jamak daridatum, berasal dari bahasa latin yang berarti "sesuatu yang diberikan". Dalam penggunaan sehari-hari data berarti suatu pernyataan yang diterima secara apa adanya. Pernyataan ini adalah hasil pengukuran atau pengamatan suatu variable yang bentuknya dapat berupa angka, kata-kata, atau citra.

2. Database

Shared collection of logically related data (and a description of this data), designed to meet the information needs of an organization.

3. Database management system

A software system that enables users to define, create, and maintain the database and that provides controlled access to this database

4. Database application program

A database application program is another program that actually uses the database to manipulate and represent data. For example, a forum system coded in PHP would use a database to store its users, posts, usage information, statistics, etc.

2. Describe the approach taken to the handling of data in the early file-based systems.

Collection of application programs that perform services for the end users (e.g. reports).

Each program defines and manages its own data

3. Describe the main characteristics of the database approach and contrast it with the file-based approach.

Arose because:

– Definition of data was embedded in application programs, rather than being stored separately and independently.

– No control over access and manipulation of data beyond that imposed by application programs.

Result:

– the database and Database Management System (DBMS).

4. Describe the five components of the DBMS environment and how they related to each other.

Data

– Used by the organization and a description of this data called the schema.

Procedures

– Instructions and rules that should be applied to the design and use of the database and DBMS.

People

Hardware

– Can range from a PC to a network of computers.

Software

– DBMS, operating system, network software (if necessary) and also the application programs.

5. Describe the advantages and disadvantages of DBMSs.

Advantages of DBMSs

1. Balanced conflicting requirements
2. Improved data accessibility and responsiveness
3. Increased productivity
4. Improved maintenance through data independence
5. Increased concurrency
6. Improved backup and recovery services

Disadvantages of DBMSs

• Complexity

• Size

• Cost of DBMS

• Additional hardware costs

• Cost of conversion

• Performance

• Higher impact of a failure