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1. What is an attribute? How is it related to an entity?

Attribute: A characteristic of an entity.

Attributes are usually selected to reflect the relevant characteristics of entities

2. Define the term database. How is it different from a database management system?

A database Collection of integrated and related files

Database management systems (DBMSs) are specially designed applications that interact with the user, other applications, and the database itself to capture and analyze data

3. What is the hierarchy of data in a database?

BitsCharacters (bytes) fields - records Files Database

4. What is a flat file?

A flat file is a simple database program whose records have no relationship to one another.

5. What is the purpose of a primary key? 1 How can it be useful in controlling data redundancy? 2

*1 a primary key is assigned to a field in a table that is completely unique

*2 Data is organized and stored in only one location

6. What is the purpose of data cleanup?

Remove inconsistencies and integrated to create a new information database that is more suitable for business analysis

7. What are the advantages of the database approach?

1: improved strategic use of corporate data

2: reduced data redundancy

3: improved data integrity

4: easier modification and updating

5: Data and program independence

6: Better access to data and info

7: Standardization of data access

8: Framework for program development

8. What is data modeling? What is its purpose? Briefly describe three commonly used data models.

Data model: A diagram of data entities and their relationships

Purpose: to define and analyze data requirements needed to support the business processes and

improves system performance

Three commonly used data models:

1: data model Diagram of data entities and relationships

2: Enterprise data modeling data modeling done at the level of entire enterprise

3: entity-relationship diagram data models that use basic graphical symbols

9. What is a database schema, and what is its purpose?

Database schema: is its structure described in a formal language supported by the database management system (DBMS) and refers to the organization of data to create a blueprint of how a database will be constructed.

Purpose: Is a way to logically group objects such as tables, views, and stored procedures etc...

10. How can a data dictionary be useful to database administrators and DBMS software engineers?

"Data dictionary contains detailed information such names of data items , aliases , range of values that can be used , type of data and amount of storage needed for these items .

FOR DB Administrator : these information are valuable in maintaining a database efficiently with a reliable storage of information with no redundancy , and make it easier to modify the data bases when necessary .

FOR DBMS software : data dictionary also help computer and systems who requires a detailed description about data elements stored in data base ."

11. Identify important characteristics in selecting a database management system.

1: database size

2: database cost

3: concurrent users

4: performance

5: integration

6: vendor

12. What is the difference between a data definition language (DDL) and a data manipulation language (DML)?

Data definition language (DDL) a collection of instructions and commands used to define and describe data and relationships in a specific database.

Data manipulation language (DML) the commands that are used to manipulate the data in a database

13. What is the difference between projecting and joining?

Projecting: Manipulating data to eliminate columns in a table

Joining: Manipulating data to combine two or more tables

14. What is a distributed database system?

A distributed database system: is a database in which storage devices are not all attached to a common processing unit such as the CPU, controlled by a distributed database management system

15. What is a data warehouse, and how is it different from a traditional database used to support OLTP?

Data warehouse: A database that collects business information from many sources in the enterprise, covering all aspects of the company’s processes, products, and customers

Difference:

Characteristics OLTP Data warehouse

Purpose Support transaction processing Support Decision making

Source of data Business Transaction Multiple files,databases

Ease of process Routine and easy Complex

16. What is meant by the “front end” and the “back end” of a DBMS?

A front-end applications one that directly interacts with people or users.

A back-end application interacts with other programs or applications

17. What is data mining? What is OLAP? How are they different?

Data mining: An information-analysis tool that involves the automated discovery of patterns and relationships in a data warehouse

Online analytical processing (OLAP) Software that allows users to explore data from a number of perspectives

Differences

OLAP tools provides multidimensional data analysis and they provide summaries of the data but contrastingly,

Data mining focuses on ratios, patterns and influences in the set of data.

18. What is an ORDBMS? What kind of data can it handle?

Object-relational database management system(ORDBMS) A DBMS capable of manipulating audio, video, and graphical data.

Audio,

Images,

Unstructured text,

Spatial or time series data.

19. What is business intelligence? How is it used?

Business intelligence the process of gathering enough of the right information in a timely manner and usable form and analyzing it to have a positive impact on business strategy, tactics, or operations.

How is it used?

Business intelligence turns data into useful information that is then distributed throughout an enterprise. It provides insight into the causes of problems, and when Implemented can improve business operations and sometimes even save lives.

20. In what circumstances might a database administrator consider using an object-oriented database?

*When there is needed to use Instructions to manipulate database

For example consider a database store monthly expenses

ORDB can do the instructions to compute a monthly budget from those expenses,

Where a traditional DBMS can’t compute, only store those monthly expenses.

And when a database contains complex data that needs to be processed quickly and efficiently